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Physics guideFirst assessment 2016

Physics guideFirst assessment 2016

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International Baccalaureate, Baccalauréat International and Bachillerato Internacional are registered trademarks of the International Baccalaureate Organization.

Published February 2014

Published on behalf of the International Baccalaureate Organization, a not-for-profit educational foundation of 15 Route des Morillons, 1218 Le Grand-Saconnex, Geneva,

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© International Baccalaureate Organization 2014

The International Baccalaureate Organization (known as the IB) offers four high-quality and challenging educational programmes for a worldwide community of schools, aiming to create a better, more peaceful world. This publication is one of a range of materials produced to support these programmes.

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Diploma ProgrammePhysics guide

IB mission statementThe International Baccalaureate aims to develop inquiring, knowledgeable and caring young people who help to create a better and more peaceful world through intercultural understanding and respect.

To this end the organization works with schools, governments and international organizations to develop challenging programmes of international education and rigorous assessment.

These programmes encourage students across the world to become active, compassionate and lifelong learners who understand that other people, with their differences, can also be right.

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Contents

Introduction 1Purpose of this document 1

The Diploma Programme 2

Nature of science 6

Nature of physics 12

Aims 17

Assessment objectives 18

Syllabus 19Syllabus outline 19

Approaches to the teaching and learning of physics 20

Syllabus content 25

Assessment 130Assessment in the Diploma Programme 130

Assessment outline—SL 132

Assessment outline—HL 133

External assessment 134

Internal assessment 136

Appendices 154Glossary of command terms 154

Bibliography 157

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Purpose of this document

Introduction

This publication is intended to guide the planning, teaching and assessment of the subject in schools. Subject teachers are the primary audience, although it is expected that teachers will use the guide to inform students and parents about the subject.

This guide can be found on the subject page of the online curriculum centre (OCC) at http://occ.ibo.org, a password-protected IB website designed to support IB teachers. It can also be purchased from the IB store at http://store.ibo.org.

Additional resourcesAdditional publications such as teacher support materials, subject reports, internal assessment guidance and grade descriptors can also be found on the OCC. Past examination papers as well as markschemes can be purchased from the IB store.

Teachers are encouraged to check the OCC for additional resources created or used by other teachers. Teachers can provide details of useful resources, for example: websites, books, videos, journals or teaching ideas.

AcknowledgmentThe IB wishes to thank the educators and associated schools for generously contributing time and resources to the production of this guide.

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Introduction

The Diploma Programme

The Diploma Programme is a rigorous pre-university course of study designed for students in the 16 to 19 age range. It is a broad-based two-year course that aims to encourage students to be knowledgeable and inquiring, but also caring and compassionate. There is a strong emphasis on encouraging students to develop intercultural understanding, open-mindedness, and the attitudes necessary for them to respect and evaluate a range of points of view.

The Diploma Programme modelThe course is presented as six academic areas enclosing a central core (see figure 1). It encourages the concurrent study of a broad range of academic areas. Students study: two modern languages (or a modern language and a classical language); a humanities or social science subject; an experimental science; mathematics; one of the creative arts. It is this comprehensive range of subjects that makes the Diploma Programme a demanding course of study designed to prepare students effectively for university entrance. In each of the academic areas students have flexibility in making their choices, which means they can choose subjects that particularly interest them and that they may wish to study further at university.

Figure 1Diploma Programme model


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Choosing the right combinationStudents are required to choose one subject from each of the six academic areas, although they can, instead of an arts subject, choose two subjects from another area. Normally, three subjects (and not more than four) are taken at higher level (HL), and the others are taken at standard level (SL). The IB recommends 240 teaching hours for HL subjects and 150 hours for SL. Subjects at HL are studied in greater depth and breadth than at SL.

At both levels, many skills are developed, especially those of critical thinking and analysis. At the end of the course, students’ abilities are measured by means of external assessment. Many subjects contain some element of coursework assessed by teachers.

The core of the Diploma Programme ModelAll Diploma Programme students participate in the three course elements that make up the core of the model. Theory of knowledge (TOK) is a course that is fundamentally about critical thinking and inquiry into the process of knowing rather than about learning a specific body of knowledge. The TOK course examines the nature of knowledge and how we know what we claim to know. It does this by encouraging students to analyse knowledge claims and explore questions about the construction of knowledge. The task of TOK is to emphasize connections between areas of shared knowledge and link them to personal knowledge in such a way that an individual becomes more aware of his or her own perspectives and how they might differ from others.

Creativity, action, service (CAS) is at the heart of the Diploma Programme. The emphasis in CAS is on helping students to develop their own identities, in accordance with the ethical principles embodied in the IB mission statement and the IB learner profile. It involves students in a range of activities alongside their academic studies throughout the Diploma Programme. The three strands of CAS are Creativity (arts, and other experiences that involve creative thinking), Action (physical exertion contributing to a healthy lifestyle) and Service (an unpaid and voluntary exchange that has a learning benefit for the student). Possibly more than any other component in the Diploma Programme, CAS contributes to the IB’s mission to create a better and more peaceful world through intercultural understanding and respect.

The extended essay, including the world studies extended essay, offers the opportunity for IB students to investigate a topic of special interest, in the form of a 4,000-word piece of independent research. The area of research undertaken is chosen from one of the students’ Diploma Programme subjects, or in the case of the interdisciplinary world studies essay, two subjects, and acquaints them with the independent research and writing skills expected at university. This leads to a major piece of formally presented, structured writing, in which ideas and findings are communicated in a reasoned and coherent manner, appropriate to the subject or subjects chosen. It is intended to promote high-level research and writing skills, intellectual discovery and creativity. As an authentic learning experience it provides students with an opportunity to engage in personal research on a topic of choice, under the guidance of a supervisor.

Approaches to teaching and approaches to learningApproaches to teaching and learning across the Diploma Programme refers to deliberate strategies, skills and attitudes which permeate the teaching and learning environment. These approaches and tools, intrinsically linked with the learner profile attributes, enhance student learning and assist student preparation for the Diploma Programme assessment and beyond. The aims of approaches to teaching and learning in the Diploma Programme are to:


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empower teachers as teachers of learners as well as teachers of content

empower teachers to create clearer strategies for facilitating learning experiences in which students are more meaningfully engaged in structured inquiry and greater critical and creative thinking

promote both the aims of individual subjects (making them more than course aspirations) and linking previously isolated knowledge (concurrency of learning)

encourage students to develop an explicit variety of skills that will equip them to continue to be actively engaged in learning after they leave school, and to help them not only obtain university admission through better grades but also prepare for success during tertiary education and beyond

enhance further the coherence and relevance of the students’ Diploma Programme experience

allow schools to identify the distinctive nature of an IB Diploma Programme education, with its blend of idealism and practicality.

The five approaches to learning (developing thinking skills, social skills, communication skills, self-management skills and research skills) along with the six approaches to teaching (teaching that is inquiry-based, conceptually focused, contextualized, collaborative, differentiated and informed by assessment) encompass the key values and principles that underpin IB pedagogy.

The IB mission statement and the IB learner profileThe Diploma Programme aims to develop in students the knowledge, skills and attitudes they will need to fulfill the aims of the IB, as expressed in the organization’s mission statement and the learner profile. Teaching and learning in the Diploma Programme represent the reality in daily practice of the organization’s educational philosophy.

Academic honestyAcademic honesty in the Diploma Programme is a set of values and behaviours informed by the attributes of the learner profile. In teaching, learning and assessment, academic honesty serves to promote personal integrity, engender respect for the integrity of others and their work, and ensure that all students have an equal opportunity to demonstrate the knowledge and skills they acquire during their studies.

All coursework—including work submitted for assessment—is to be authentic, based on the student’s individual and original ideas with the ideas and work of others fully acknowledged. Assessment tasks that require teachers to provide guidance to students or that require students to work collaboratively must be completed in full compliance with the detailed guidelines provided by the IB for the relevant subjects.

For further information on academic honesty in the IB and the Diploma Programme, please consult the IB publications Academic honesty, The Diploma Programme: From principles into practice and General regulations: Diploma Programme. Specific information regarding academic honesty as it pertains to external and internal assessment components of this Diploma Programme subject can be found in this guide.

Acknowledging the ideas or work of another personCoordinators and teachers are reminded that candidates must acknowledge all sources used in work submitted for assessment. The following is intended as a clarification of this requirement.

Diploma Programme candidates submit work for assessment in a variety of media that may include audio-visual material, text, graphs, images and/or data published in print or electronic sources. If a candidate uses the work or ideas of another person, the candidate must acknowledge the source using a standard style of


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referencing in a consistent manner. A candidate’s failure to acknowledge a source will be investigated by the IB as a potential breach of regulations that may result in a penalty imposed by the IB final award committee.

The IB does not prescribe which style(s) of referencing or in-text citation should be used by candidates; this is left to the discretion of appropriate faculty/staff in the candidate’s school. The wide range of subjects, three response languages and the diversity of referencing styles make it impractical and restrictive to insist on particular styles. In practice, certain styles may prove most commonly used, but schools are free to choose a style that is appropriate for the subject concerned and the language in which candidates’ work is written. Regardless of the reference style adopted by the school for a given subject, it is expected that the minimum information given includes: name of author, date of publication, title of source, and page numbers as applicable.

Candidates are expected to use a standard style and use it consistently so that credit is given to all sources used, including sources that have been paraphrased or summarized. When writing, candidates must clearly distinguish between their words and those of others by the use of quotation marks (or other method, such as indentation) followed by an appropriate citation that denotes an entry in the bibliography. If an electronic source is cited, the date of access must be indicated. Candidates are not expected to show faultless expertise in referencing, but are expected to demonstrate that all sources have been acknowledged. Candidates must be advised that audio-visual material, text, graphs, images and/or data published in print or in electronic sources that is not their own must also attribute the source. Again, an appropriate style of referencing/citation must be used.

Learning diversity and learning support requirementsSchools must ensure that equal access arrangements and reasonable adjustments are provided to candidates with learning support requirements that are in line with the IB documents Candidates with assessment access requirements and Learning diversity within the International Baccalaureate programmes/Special educational needs within the International Baccalaureate programmes.

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The Nature of science (NOS) is an overarching theme in the biology, chemistry and physics courses. This section, titled “Nature of science”, is in the biology, chemistry and physics guides to support teachers in their understanding of what is meant by the nature of science. The “Nature of science” section of the guide provides a comprehensive account of the nature of science in the 21st century. It will not be possible to cover in this document all the themes in detail in the three science courses, either for teaching or assessment.

It has a paragraph structure (1.1, 1.2, etc) to link the significant points made to the syllabus (landscape pages) references on the NOS. The NOS parts in the subject-specific sections of the guide are examples of a particular understanding. The NOS statement(s) above every sub-topic outline how one or more of the NOS themes can be exemplified through the understandings, applications and skills in that sub-topic. These are not a repeat of the NOS statements found below but an elaboration of them in a specific context. See the section on “Format of the syllabus”.

TechnologyAlthough this section is about the nature of science, the interpretation of the word technology is important, and the role of technology emerging from and contributing to science needs to be clarified. In today’s world, the words science and technology are often used interchangeably; however, historically this is not the case. Technology emerged before science, and materials were used to produce useful and decorative artefacts long before there was an understanding of why materials had different properties that could be used for different purposes. In the modern world the reverse is the case: an understanding of the underlying science is the basis for technological developments. These new technologies in their turn drive developments in science.

Despite their mutual dependence they are based on different values: science on evidence, rationality and the quest for deeper understanding; technology on the practical, the appropriate and the useful with an increasingly important emphasis on sustainability.

1. What is science and what is the scientific endeavour?

1.1. The underlying assumption of science is that the universe has an independent, external reality accessible to human senses and amenable to human reason.

1.2. Pure science aims to come to a common understanding of this external universe; applied science and engineering develop technologies that result in new processes and products. However, the boundaries between these fields are fuzzy.

1.3. Scientists use a wide variety of methodologies which, taken together, make up the process of science. There is no single “scientific method”. Scientists have used, and do use, different methods at different times to build up their knowledge and ideas, but they have a common understanding about what makes them all scientifically valid.

1.4. This is an exciting and challenging adventure involving much creativity and imagination as well as exacting and detailed thinking and application. Scientists also have to be ready for unplanned, surprising, accidental discoveries. The history of science shows this is a very common occurrence.

1.5. Many scientific discoveries have involved flashes of intuition and many have come from speculation or simple curiosity about particular phenomena.

Nature of science

Introduction

Nature of science

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1.6. Scientists have a common terminology and a common reasoning process, which involves using deductive and inductive logic through analogies and generalizations. They share mathematics, the language of science, as a powerful tool. Indeed, some scientific explanations only exist in mathematical form.

1.7. Scientists must adopt a skeptical attitude to claims. This does not mean that they disbelieve everything, but rather that they suspend judgment until they have a good reason to believe a claim to be true or false. Such reasons are based on evidence and argument.

1.8. The importance of evidence is a fundamental common understanding. Evidence can be obtained by observation or experiment. It can be gathered by human senses, primarily sight, but much modern science is carried out using instrumentation and sensors that can gather information remotely and automatically in areas that are too small, or too far away, or otherwise beyond human sense perception. Improved instrumentation and new technology have often been the drivers for new discoveries. Observations followed by analysis and deduction led to the Big Bang theory of the origin of the universe and to the theory of evolution by natural selection. In these cases, no controlled experiments were possible. Disciplines such as geology and astronomy rely strongly on collecting data in the field, but all disciplines use observation to collect evidence to some extent. Experimentation in a controlled environment, generally in laboratories, is the other way of obtaining evidence in the form of data, and there are many conventions and understandings as to how this is to be achieved.

1.9. This evidence is used to develop theories, generalize from data to form laws and propose hypotheses. These theories and hypotheses are used to make predictions that can be tested. In this way theories can be supported or opposed and can be modified or replaced by new theories.

1.10. Models, some simple, some very complex, based on theoretical understanding, are developed to explain processes that may not be observable. Computer-based mathematical models are used to make testable predictions, which can be especially useful when experimentation is not possible. Models tested against experiments or data from observations may prove inadequate, in which case they may be modified or replaced by new models.

1.11. The outcomes of experiments, the insights provided by modelling and observations of the natural world may be used as further evidence for a claim.

1.12. The growth in computing power has made modelling much more powerful. Models, usually mathematical, are now used to derive new understandings when no experiments are possible (and sometimes when they are). This dynamic modelling of complex situations involving large amounts of data, a large number of variables and complex and lengthy calculations is only possible as a result of increased computing power. Modelling of the Earth’s climate, for example, is used to predict or make a range of projections of future climatic conditions. A range of different models has been developed in this field and results from different models have been compared to see which models are most accurate. Models can sometimes be tested by using data from the past and used to see if they can predict the present situation. If a model passes this test, we gain confidence in its accuracy.

1.13. Both the ideas and the processes of science can only occur in a human context. Science is carried out by a community of people from a wide variety of backgrounds and traditions, and this has clearly influenced the way science has proceeded at different times. It is important to understand, however, that to do science is to be involved in a community of inquiry with certain common principles, methodologies, understandings and processes.

2. The understanding of science2.1. Theories, laws and hypotheses are concepts used by scientists. Though these concepts are connected,

there is no progression from one to the other. These words have a special meaning in science and it is important to distinguish these from their everyday use.

2.2. Theories are themselves integrated, comprehensive models of how the universe, or parts of it, work. A theory can incorporate facts and laws and tested hypotheses. Predictions can be made from the theories and these can be tested in experiments or by careful observations. Examples are the germ theory of disease or atomic theory.

2.3. Theories generally accommodate the assumptions and premises of other theories, creating a consistent understanding across a range of phenomena and disciplines. Occasionally, however, a new theory will radically change how essential concepts are understood or framed, impacting other theories and causing what is sometimes called a “paradigm shift” in science. One of the most famous paradigm shifts in science occurred when our idea of time changed from an absolute frame of reference to an observer-dependent frame of reference within Einstein’s theory of relativity. Darwin’s theory of evolution by natural selection also changed our understanding of life on Earth.

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2.4. Laws are descriptive, normative statements derived from observations of regular patterns of behaviour. They are generally mathematical in form and can be used to calculate outcomes and to make predictions. Like theories and hypotheses, laws cannot be proven. Scientific laws may have exceptions and may be modified or rejected based on new evidence. Laws do not necessarily explain a phenomenon. For example, Newton’s law of universal gravitation tells us that the force between two masses is inversely proportional to the square of the distance between them, and allows us to calculate the force between masses at any distance apart, but it does not explain why masses attract each other. Also, note that the term law has been used in different ways in science, and whether a particular idea is called a law may be partly a result of the discipline and time period at which it was developed.

2.5. Scientists sometimes form hypotheses—explanatory statements about the world that could be true or false, and which often suggest a causal relationship or a correlation between factors. Hypotheses can be tested by both experiments and observations of the natural world and can be supported or opposed.

2.6. To be scientific, an idea (for example, a theory or hypothesis) must focus on the natural world and natural explanations and must be testable. Scientists strive to develop hypotheses and theories that are compatible with accepted principles and that simplify and unify existing ideas.

2.7. The principle of Occam’s razor is used as a guide to developing a theory. The theory should be as simple as possible while maximizing explanatory power.

2.8. The ideas of correlation and cause are very important in science. A correlation is a statistical link or association between one variable and another. A correlation can be positive or negative and a correlation coefficient can be calculated that will have a value between +1, 0 and −1. A strong correlation (positive or negative) between one factor and another suggests some sort of causal relationship between the two factors but more evidence is usually required before scientists accept the idea of a causal relationship. To establish a causal relationship, ie one factor causing another, scientists need to have a plausible scientific mechanism linking the factors. This strengthens the case that one causes the other, for example smoking and lung cancer. This mechanism can be tested in experiments.

2.9. The ideal situation is to investigate the relationship between one factor and another while controlling all other factors in an experimental setting; however, this is often impossible and scientists, especially in biology and medicine, use sampling, cohort studies and case control studies to strengthen their understanding of causation when experiments (such as double-blind tests and clinical trials) are not possible. Epidemiology in the field of medicine involves the statistical analysis of data to discover possible correlations when little established scientific knowledge is available or the circumstances are too difficult to control entirely. Here, as in other fields, mathematical analysis of probability also plays a role.

3. The objectivity of science3.1. Data is the lifeblood of scientists and may be qualitative or quantitative. It can be obtained purely from

observations or from specifically designed experiments, remotely using electronic sensors or by direct measurement. The best data for making accurate and precise descriptions and predictions is often quantitative and amenable to mathematical analysis. Scientists analyse data and look for patterns, trends and discrepancies, attempting to discover relationships and establish causal links. This is not always possible, so identifying and classifying observations and artefacts (eg types of galaxies or fossils) is still an important aspect of scientific work.

3.2. Taking repeated measurements and large numbers of readings can improve reliability in data collection. Data can be presented in a variety of formats such as linear and logarithmic graphs that can be analysed for, say, direct or inverse proportion or for power relationships.

3.3. Scientists need to be aware of random errors and systematic errors, and use techniques such as error bars and lines of best fit on graphs to portray the data as realistically and honestly as possible. There is a need to consider whether outlying data points should be discarded or not.

3.4. Scientists need to understand the difference between errors and uncertainties, accuracy and precision, and need to understand and use the mathematical ideas of average, mean, mode, median, etc. Statistical methods such as standard deviation and chi-squared tests are often used. It is important to be able to assess how accurate a result is. A key part of the training and skill of scientists is in being able to decide which technique is appropriate in different circumstances.

3.5. It is also very important for scientists to be aware of the cognitive biases that may impact experimental design and interpretation. The confirmation bias, for example, is a well-documented cognitive bias that urges us to find reasons to reject data that is unexpected or does not conform to our expectations or desires, and to perhaps too readily accept data that agrees with these expectations or desires. The processes and methodologies of science are largely designed to account for these biases. However, care must always be taken to avoid succumbing to them.

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3.6. Although scientists cannot ever be certain that a result or finding is correct, we know that some scientific results are very close to certainty. Scientists often speak of “levels of confidence” when discussing outcomes. The discovery of the existence of a Higgs boson is such an example of a “level of confidence”. This particle may never be directly observable, but to establish its “existence” particle physicists had to pass the self-imposed definition of what can be regarded as a discovery—the 5-sigma “level of certainty”—or about a 0.00003% chance that the effect is not real based on experimental evidence.

3.7. In recent decades, the growth in computing power, sensor technology and networks has allowed scientists to collect large amounts of data. Streams of data are downloaded continuously from many sources such as remote sensing satellites and space probes and large amounts of data are generated in gene sequencing machines. Experiments in CERN’s Large Hadron Collider regularly produce 23 petabytes of data per second, which is equivalent to 13.3 years of high definition TV content per second.

3.8. Research involves analysing large amounts of this data, stored in databases, looking for patterns and unique events. This has to be done using software that is generally written by the scientists involved. The data and the software may not be published with the scientific results but would be made generally available to other researchers.

4. The human face of science4.1. Science is highly collaborative and the scientific community is composed of people working in science,

engineering and technology. It is common to work in teams from many disciplines so that different areas of expertise and specializations can contribute to a common goal that is beyond one scientific field. It is also the case that how a problem is framed in the paradigm of one discipline might limit possible solutions, so framing problems using a variety of perspectives, in which new solutions are possible, can be extremely useful.

4.2. Teamwork of this sort takes place with the common understanding that science should be open-minded and independent of religion, culture, politics, nationality, age and gender. Science involves the free global interchange of information and ideas. Of course, individual scientists are human and may have biases and prejudices, but the institutions, practices and methodologies of science help keep the scientific endeavour as a whole unbiased.

4.3. As well as collaborating on the exchange of results, scientists work on a daily basis in collaborative groups on a small and large scale within and between disciplines, laboratories, organizations and countries, facilitated even more by virtual communication. Examples of large-scale collaboration include:

– The Manhattan project, the aim of which was to build and test an atomic bomb. It eventually employed more than 130,000 people and resulted in the creation of multiple production and research sites that operated in secret, culminating in the dropping of two atomic bombs on Hiroshima and Nagasaki.

– The Human Genome Project (HGP), which was an international scientific research project set up to map the human genome. The $3-billion project beginning in 1990 produced a draft of the genome in 2000. The sequence of the DNA is stored in databases available to anyone on the internet.

– The IPCC (Intergovernmental Panel on Climate Change), organized under the auspices of the United Nations, is officially composed of about 2,500 scientists. They produce reports summarizing the work of many more scientists from all around the world.

– CERN, the European Organization for Nuclear Research, an international organization set up in 1954, is the world’s largest particle physics laboratory. The laboratory, situated in Geneva, employs about 2,400 people and shares results with 10,000 scientists and engineers covering over 100 nationalities from 600 or more universities and research facilities.

All the above examples are controversial to some degree and have aroused emotions among scientists and the public.

4.4. Scientists spend a considerable amount of time reading the published results of other scientists. They publish their own results in scientific journals after a process called peer review. This is when the work of a scientist or, more usually, a team of scientists is anonymously and independently reviewed by several scientists working in the same field who decide if the research methodologies are sound and if the work represents a new contribution to knowledge in that field. They also attend conferences

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to make presentations and display posters of their work. Publication of peer-reviewed journals on the internet has increased the efficiency with which the scientific literature can be searched and accessed. There are a large number of national and international organizations for scientists working in specialized areas within subjects.

4.5. Scientists often work in areas, or produce findings, that have significant ethical and political implications. These areas include cloning, genetic engineering of food and organisms, stem cell and reproductive technologies, nuclear power, weapons development (nuclear, chemical and biological), transplantation of tissue and organs and in areas that involve testing on animals (see IB animal experimentation policy). There are also questions involving intellectual property rights and the free exchange of information that may impact significantly on a society. Science is undertaken in universities, commercial companies, government organizations, defence agencies and international organizations. Questions of patents and intellectual property rights arise when work is done in a protected environment.

4.6. The integrity and honest representation of data is paramount in science—results should not be fixed or manipulated or doctored. To help ensure academic honesty and guard against plagiarism, all sources are quoted and appropriate acknowledgment made of help or support. Peer review and the scrutiny and skepticism of the scientific community also help achieve these goals.

4.7. All science has to be funded and the source of the funding is crucial in decisions regarding the type of research to be conducted. Funding from governments and charitable foundations is sometimes for pure research with no obvious direct benefit to anyone, whereas funding from private companies is often for applied research to produce a particular product or technology. Political and economic factors often determine the nature and extent of the funding. Scientists often have to spend time applying for research grants and have to make a case for what they want to research.

4.8. Science has been used to solve many problems and improve humankind’s lot, but it has also been used in morally questionable ways and in ways that inadvertently caused problems. Advances in sanitation, clean water supplies and hygiene led to significant decreases in death rates but without compensating decreases in birth rates, this led to huge population increases with all the problems of resources, energy and food supplies that entails. Ethical discussions, risk–benefit analyses, risk assessment and the precautionary principle are all parts of the scientific way of addressing the common good.

5. Scientific literacy and the public understanding of science

5.1. An understanding of the nature of science is vital when society needs to make decisions involving scientific findings and issues. How does the public judge? It may not be possible to make judgments based on the public’s direct understanding of a science, but important questions can be asked about whether scientific processes were followed and scientists have a role in answering such questions.

5.2. As experts in their particular fields, scientists are well placed to explain to the public their issues and findings. Outside their specializations, they may be no more qualified than ordinary citizens to advise others on scientific issues, although their understanding of the processes of science can help them to make personal decisions and to educate the public as to whether claims are scientifically credible.

5.3. As well as comprising knowledge of how scientists work and think, scientific literacy involves being aware of faulty reasoning. There are many cognitive biases/fallacies of reasoning to which people are susceptible (including scientists) and these need to be corrected whenever possible. Examples of these are the confirmation bias, hasty generalizations, post hoc ergo propter hoc (false cause), the straw man fallacy, redefinition (moving the goal posts), the appeal to tradition, false authority and the accumulation of anecdotes being regarded as evidence.

5.4. When such biases and fallacies are not properly managed or corrected, or when the processes and checks and balances of science are ignored or misapplied, the result is pseudoscience. Pseudoscience is the term applied to those beliefs and practices that claim to be scientific but do not meet or follow the standards of proper scientific methodologies, ie they lack supporting evidence or a theoretical framework, are not always testable and hence falsifiable, are expressed in a non-rigorous or unclear manner and often fail to be supported by scientific testing.

5.5. Another key issue is the use of appropriate terminology. Words that scientists agree on as being scientific terms will often have a different meaning in everyday life and scientific discourse with the public needs to take this into account. For example, a theory in everyday use means a hunch or speculation, but in science an accepted theory is a scientific idea that has produced predictions that have been thoroughly tested in many different ways. An aerosol is just a spray can to the general public, but in science it is a suspension of solid or liquid particles in a gas.

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5.6. Whatever the field of science—whether it is in pure research, applied research or in engineering new technology—there is boundless scope for creative and imaginative thinking. Science has achieved a great deal but there are many, many unanswered questions to challenge future scientists.

The flow chart below is part of an interactive flow chart showing the scientific process of inquiry in practice. The interactive version can be found at “How science works: The flowchart.” Understanding Science. University of California Museum of Paleontology. 1 February 2013 <http://undsci.berkeley.edu/article/scienceflowchart>.

Figure 2

Pathways to scientific discovery

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Nature of physics

Introduction

“Physics is a tortured assembly of contrary qualities: of scepticism and rationality, of freedom and revolution, of passion and aesthetics, and of soaring imagination and trained common sense.”

Leon M Lederman (Nobel Prize for Physics, 1988)

Physics is the most fundamental of the experimental sciences, as it seeks to explain the universe itself from the very smallest particles—currently accepted as quarks, which may be truly fundamental—to the vast distances between galaxies.

Classical physics, built upon the great pillars of Newtonian mechanics, electromagnetism and thermodynamics, went a long way in deepening our understanding of the universe. From Newtonian mechanics came the idea of predictability in which the universe is deterministic and knowable. This led to Laplace’s boast that by knowing the initial conditions—the position and velocity of every particle in the universe—he could, in principle, predict the future with absolute certainty. Maxwell’s theory of electromagnetism described the behaviour of electric charge and unified light and electricity, while thermodynamics described the relation between energy transferred due to temperature difference and work and described how all natural processes increase disorder in the universe.

However, experimental discoveries dating from the end of the 19th century eventually led to the demise of the classical picture of the universe as being knowable and predictable. Newtonian mechanics failed when applied to the atom and has been superseded by quantum mechanics and general relativity. Maxwell’s theory could not explain the interaction of radiation with matter and was replaced by quantum electrodynamics (QED). More recently, developments in chaos theory, in which it is now realized that small changes in the initial conditions of a system can lead to completely unpredictable outcomes, have led to a fundamental rethinking in thermodynamics.

While chaos theory shows that Laplace’s boast is hollow, quantum mechanics and QED show that the initial conditions that Laplace required are impossible to establish. Nothing is certain and everything is decided by probability. But there is still much that is unknown and there will undoubtedly be further paradigm shifts as our understanding deepens.

Despite the exciting and extraordinary development of ideas throughout the history of physics, certain aspects have remained unchanged. Observations remain essential to the very core of physics, sometimes requiring a leap of imagination to decide what to look for. Models are developed to try to understand observations, and these themselves can become theories that attempt to explain the observations. Theories are not always directly derived from observations but often need to be created. These acts of creation can be compared to those in great art, literature and music, but differ in one aspect that is unique to science: the predictions of these theories or ideas must be tested by careful experimentation. Without these tests, a theory cannot be quantified. A general or concise statement about how nature behaves, if found to be experimentally valid over a wide range of observed phenomena, is called a law or a principle.

The scientific processes carried out by the most eminent scientists in the past are the same ones followed by working physicists today and, crucially, are also accessible to students in schools. Early in the development of science, physicists were both theoreticians and experimenters (natural philosophers). The body of scientific knowledge has grown in size and complexity, and the tools and skills of theoretical and experimental physicists have become so specialized that it is difficult (if not impossible) to be highly proficient in both

Nature of physics

Physics guide 13

areas. While students should be aware of this, they should also know that the free and rapid interplay of theoretical ideas and experimental results in the public scientific literature maintains the crucial links between these fields.

At the school level both theory and experiments should be undertaken by all students. They should complement one another naturally, as they do in the wider scientific community. The Diploma Programme physics course allows students to develop traditional practical skills and techniques and increase their abilities in the use of mathematics, which is the language of physics. It also allows students to develop interpersonal and digital communication skills which are essential in modern scientific endeavour and are important life-enhancing, transferable skills in their own right.

Alongside the growth in our understanding of the natural world, perhaps the more obvious and relevant result of physics to most of our students is our ability to change the world. This is the technological side of physics, in which physical principles have been applied to construct and alter the material world to suit our needs, and have had a profound influence on the daily lives of all human beings. This raises the issue of the impact of physics on society, the moral and ethical dilemmas, and the social, economic and environmental implications of the work of physicists. These concerns have become more prominent as our power over the environment has grown, particularly among young people, for whom the importance of the responsibility of physicists for their own actions is self-evident.

Physics is therefore, above all, a human activity, and students need to be aware of the context in which physicists work. Illuminating its historical development places the knowledge and the process of physics in a context of dynamic change, in contrast to the static context in which physics has sometimes been presented. This can give students insights into the human side of physics: the individuals; their personalities, times and social milieux; their challenges, disappointments and triumphs.

The Diploma Programme physics course includes the essential principles of the subject but also, through selection of an option, allows teachers some flexibility to tailor the course to meet the needs of their students. The course is available at both SL and HL, and therefore accommodates students who wish to study physics as their major subject in higher education and those who do not.

Teaching approachThere are a variety of approaches to the teaching of physics. By its very nature, physics lends itself to an experimental approach, and it is expected that this will be reflected throughout the course. The order in which the syllabus is arranged is not the order in which it should be taught, and it is up to individual teachers to decide on an arrangement that suits their circumstances. Sections of the option material may be taught within the core or the additional higher level (AHL) material if desired, or the option material can be taught as a separate unit.

Science and the international dimensionScience itself is an international endeavour—the exchange of information and ideas across national boundaries has been essential to the progress of science. This exchange is not a new phenomenon but it has accelerated in recent times with the development of information and communication technologies. Indeed, the idea that science is a Western invention is a myth—many of the foundations of modern-day science were laid many centuries ago by Arabic, Indian and Chinese civilizations, among others. Teachers are encouraged to emphasize this contribution in their teaching of various topics, perhaps through the use of timeline websites. The scientific method in its widest sense, with its emphasis on peer review, open-mindedness and freedom of thought, transcends politics, religion, gender and nationality. Where appropriate within certain topics, the syllabus details sections in the group 4 guides contain links illustrating the international aspects of science.

Nature of physics

Physics guide14

On an organizational level, many international bodies now exist to promote science. United Nations bodies such as UNESCO, UNEP and WMO, where science plays a prominent part, are well known, but in addition there are hundreds of international bodies representing every branch of science. The facilities for large-scale research in, for example, particle physics and the Human Genome Project are expensive, and only joint ventures involving funding from many countries allow this to take place. The data from such research is shared by scientists worldwide. Group 4 teachers and students are encouraged to access the extensive websites and databases of these international scientific organizations to enhance their appreciation of the international dimension.

Increasingly there is a recognition that many scientific problems are international in nature and this has led to a global approach to research in many areas. The reports of the Intergovernmental Panel on Climate Change are a prime example of this. On a practical level, the group 4 project (which all science students must undertake) mirrors the work of real scientists by encouraging collaboration between schools across the regions.

The power of scientific knowledge to transform societies is unparalleled. It has the potential to produce great universal benefits, or to reinforce inequalities and cause harm to people and the environment. In line with the IB mission statement, group 4 students need to be aware of the moral responsibility of scientists to ensure that scientific knowledge and data are available to all countries on an equitable basis and that they have the scientific capacity to use this for developing sustainable societies.

Students’ attention should be drawn to sections of the syllabus with links to international-mindedness. Examples of issues relating to international-mindedness are given within sub-topics in the syllabus content. Teachers could also use resources found on the Global Engage website (http://globalengage. ibo.org).

Distinction between SL and HLGroup 4 students at standard level (SL) and higher level (HL) undertake a common core syllabus, a common internal assessment (IA) scheme and have some overlapping elements in the option studied. They are presented with a syllabus that encourages the development of certain skills, attributes and attitudes, as described in the “Assessment objectives” section of the guide.

While the skills and activities of group 4 science subjects are common to students at both SL and HL, students at HL are required to study some topics in greater depth, in the additional higher level (AHL) material and in the common options. The distinction between SL and HL is one of breadth and depth.

Prior learningPast experience shows that students will be able to study a group 4 science subject at SL successfully with no background in, or previous knowledge of, science. Their approach to learning, characterized by the IB learner profile attributes, will be significant here.

However, for most students considering the study of a group 4 subject at HL, while there is no intention to restrict access to group 4 subjects, some previous exposure to formal science education would be necessary. Specific topic details are not specified but students who have undertaken the IB Middle Years Programme (MYP) or studied an equivalent national science qualification or a school-based science course would be well prepared for an HL subject.

Links to the Middle Years ProgrammeStudents who have undertaken the MYP science, design and mathematics courses will be well prepared for group 4 subjects. The alignment between MYP science and Diploma Programme group 4 courses allows for a smooth transition for students between programmes. The concurrent planning of the new group 4 courses and MYP: Next Chapter (both launched in 2014) has helped develop a closer alignment.

Nature of physics

Physics guide 15

Scientific inquiry is central to teaching and learning science in the MYP. It enables students to develop a way of thinking and a set of skills and processes that, while allowing them to acquire and use knowledge, equip them with the capabilities to tackle, with confidence, the internal assessment component of group 4 subjects. The vision of MYP sciences is to contribute to the development of students as 21st-century learners. A holistic sciences programme allows students to develop and utilize a mixture of cognitive abilities, social skills, personal motivation, conceptual knowledge and problem-solving competencies within an inquiry-based learning environment (Rhoton 2010). Inquiry aims to support students’ understanding by providing them with opportunities to independently and collaboratively investigate relevant issues through both research and experimentation. This forms a firm base of scientific understanding with deep conceptual roots for students entering group 4 courses.

In the MYP, teachers make decisions about student achievement using their professional judgment, guided by criteria that are public, precise and known in advance, ensuring that assessment is transparent. The IB describes this approach as “criterion-related”—a philosophy of assessment that is neither “norm-referenced” (where students must be compared to each other and to an expected distribution of achievement) nor “criterion-referenced” (where students must master all strands of specific criteria at lower achievement levels before they can be considered to have achieved the next level). It is important to emphasize that the single most important aim of MYP assessment (consistent with the PYP and DP) is to support curricular goals and encourage appropriate student learning. Assessments are based upon evaluating course aims and objectives and, therefore, effective teaching to the course requirements also ensures effective teaching for formal assessment requirements. Students need to understand what the assessment expectations, standards and practices are and these should all be introduced early and naturally in teaching, as well as in class and homework activities. Experience with criterion-related assessment greatly assists students entering group 4 courses with understanding internal assessment requirements.

MYP science is a concept-driven curriculum, aimed at helping the learner construct meaning through improved critical thinking and the transfer of knowledge. At the top level are key concepts which are broad, organizing, powerful ideas that have relevance within the science course but also transcend it, having relevance in other subject groups. These key concepts facilitate both disciplinary and interdisciplinary learning as well as making connections with other subjects. While the key concepts provide breadth, the related concepts in MYP science add depth to the programme. The related concept can be considered to be the big idea of the unit which brings focus and depth and leads students towards the conceptual understanding.

Across the MYP there are 16 key concepts with the three highlighted below the focus for MYP science.

The key concepts across the MYP curriculum

Aesthetics Change Communication Communities

Connections Creativity Culture Development

Form Global interactions Identity Logic

Perspective Relationships Systems Time, place and space

MYP students may in addition undertake an optional onscreen concept-based assessment as further preparation for Diploma Programme science courses.

Nature of physics

Physics guide16

Science and theory of knowledgeThe theory of knowledge (TOK) course (first assessment 2015) engages students in reflection on the nature of knowledge and on how we know what we claim to know. The course identifies eight ways of knowing: reason, emotion, language, sense perception, intuition, imagination, faith and memory. Students explore these means of producing knowledge within the context of various areas of knowledge: the natural sciences, the social sciences, the arts, ethics, history, mathematics, religious knowledge systems and indigenous knowledge systems. The course also requires students to make comparisons between the different areas of knowledge, reflecting on how knowledge is arrived at in the various disciplines, what the disciplines have in common, and the differences between them.

TOK lessons can support students in their study of science, just as the study of science can support students in their TOK course. TOK provides a space for students to engage in stimulating wider discussions about questions such as what it means for a discipline to be a science, or whether there should be ethical constraints on the pursuit of scientific knowledge. It also provides an opportunity for students to reflect on the methodologies of science, and how these compare to the methodologies of other areas of knowledge. It is now widely accepted that there is no one scientific method, in the strict Popperian sense. Instead, the sciences utilize a variety of approaches in order to produce explanations for the behaviour of the natural world. The different scientific disciplines share a common focus on utilizing inductive and deductive reasoning, on the importance of evidence, and so on. Students are encouraged to compare and contrast these methods with the methods found in, for example, the arts or in history.

In this way there are rich opportunities for students to make links between their science and TOK courses. One way in which science teachers can help students to make these links to TOK is by drawing students’ attention to knowledge questions that arise from their subject content. Knowledge questions are open-ended questions about knowledge such as:

How do we distinguish science from pseudoscience?

When performing experiments, what is the relationship between a scientist’s expectation and their perception?

How does scientific knowledge progress?

What is the role of imagination and intuition in the sciences?

What are the similarities and differences in methods in the natural sciences and the human sciences?

Examples of relevant knowledge questions are provided throughout this guide within the sub-topics in the syllabus content. Teachers can also find suggestions of interesting knowledge questions for discussion in the “Areas of knowledge” and “Knowledge frameworks” sections of the TOK guide. Students should be encouraged to raise and discuss such knowledge questions in both their science and TOK classes.

Physics guide 1717

Aims

Group 4 aimsThrough studying biology, chemistry or physics, students should become aware of how scientists work and communicate with each other. While the scientific method may take on a wide variety of forms, it is the emphasis on a practical approach through experimental work that characterizes these subjects.

The aims enable students, through the overarching theme of the Nature of science, to:

1. appreciate scientific study and creativity within a global context through stimulating and challenging opportunities

2. acquire a body of knowledge, methods and techniques that characterize science and technology

3. apply and use a body of knowledge, methods and techniques that characterize science and technology

4. develop an ability to analyse, evaluate and synthesize scientific information

5. develop a critical awareness of the need for, and the value of, effective collaboration and communication during scientific activities

6. develop experimental and investigative scientific skills including the use of current technologies

7. develop and apply 21st-century communication skills in the study of science

8. become critically aware, as global citizens, of the ethical implications of using science and technology

9. develop an appreciation of the possibilities and limitations of science and technology

10. develop an understanding of the relationships between scientific disciplines and their influence on other areas of knowledge.

Introduction

Physics guide1818

Introduction

The assessment objectives for biology, chemistry and physics reflect those parts of the aims that will be formally assessed either internally or externally. These assessments will centre upon the nature of science. It is the intention of these courses that students are able to fullfill the following assessment objectives:

1. Demonstrate knowledge and understanding of:

a. facts, concepts and terminology

b. methodologies and techniques

c. communicating scientific information.

2. Apply:

a. facts, concepts and terminology


c. methods of communicating scientific information.

3. Formulate, analyse and evaluate:

a. hypotheses, research questions and predictions


c. primary and secondary data

d. scientific explanations.

4. Demonstrate the appropriate research, experimental, and personal skills necessary to carry out insightful and ethical investigations.

Assessment objectives

Physics guide 1919

Syllabus outline

Syllabus

Syllabus component

Recommendedteaching hours

SL HL

Core1. Measurements and uncertainties

2. Mechanics

3. Thermal physics

4. Waves

5. Electricity and magnetism

6. Circular motion and gravitation

7. Atomic, nuclear and particle physics

8. Energy production

95

5

22

11

15

15

5

14

8

Additional higher level (AHL)9. Wave phenomena

10. Fields

11. Electromagnetic induction

12. Quantum and nuclear physics

60

17

11

16

16

OptionA. Relativity

B. Engineering physics

C. Imaging

D. Astrophysics

15

15

15

15

15

25

25

25

25

25

Practical scheme of workPractical activities

Individual investigation (internal assessment – IA)

Group 4 project

40

20

10

10

60

40

10

10

Total teaching hours 150 240

The recommended teaching time is 240 hours to complete HL courses and 150 hours to complete SL courses as stated in the document General regulations: Diploma Programme for students and their legal guardians (page 4, article 8.2).

Physics guide2020

Syllabus

Format of the syllabusThe format of the syllabus section of the group 4 guides is the same for each subject. This new structure gives prominence and focus to the teaching and learning aspects.

Topics or optionsTopics are numbered and options are indicated by a letter. For example, “Topic 8: Energy production”, or “Option D: Astrophysics”.

Sub-topicsSub-topics are numbered as follows, “6.1 – Circular motion”. Further information and guidance about possible teaching times are contained in the teacher support material.

Each sub-topic begins with an essential idea. The essential idea is an enduring interpretation that is considered part of the public understanding of science. This is followed by a section on the “Nature of science”. This gives specific examples in context illustrating some aspects of the nature of science. These are linked directly to specific references in the “Nature of science” section of the guide to support teachers in their understanding of the general theme to be addressed.

Under the overarching “Nature of science” theme there are two columns. The first column lists “Understandings”, which are the main general ideas to be taught. There follows an “Applications and skills” section that outlines the specific applications and skills to be developed from the understandings. A “Guidance” section gives information about the limits and constraints and the depth of treatment required for teachers and examiners. The contents of the “Nature of science” section above the two columns and contents of the first column are all legitimate items for assessment. In addition, some assessment of international-mindedness in science, from the content of the second column, will be assessed as in the previous course.

The second column gives suggestion to teachers about relevant references to international-mindedness. It also gives examples of TOK knowledge questions (see Theory of knowledge guide published 2013) that can be used to focus students’ thoughts on the preparation of the TOK prescribed essay title. The links section may link the sub-topic to other parts of the subject syllabus, to other Diploma Programme subject guides or to real-world applications. Finally, the “Aims” section refers to how specific group 4 aims are being addressed in the sub-topic.

Approaches to the teaching and learning of physics


Physics guide 21

Format of the guideTopic 1: <Title>

Essential idea: This lists the essential idea for each sub-topic.

1.1 Sub-topic

Nature of science: Relates the sub-topic to the overarching theme of NOS.

Understandings:

This section will provide specifics of the content requirements for each sub-topic.

Applications and skills:

The content of this section gives details of how students are to apply the understandings. For example, these applications could involve demonstrating mathematical calculations or practical skills.

Guidance:

This section will provide specifics and give constraints to the requirements for the understandings and applications and skills.

Data booklet reference:

This section will include links to specific sections in the data booklet.

International-mindedness:

Ideas that teachers can easily integrate into the delivery of their lessons.

Theory of knowledge:

Examples of TOK knowledge questions.

Utilization:

Links to other topics within the Physics guide, to a variety of real-world applications and to other Diploma Programme courses.

Aims:

Links to the group 4 subject aims.

Group 4 experimental skillsI hear and I forget. I see and I remember. I do and I understand.

Confucius

Integral to the experience of students in any of the group 4 courses is their experience in the classroom laboratory or in the field. Practical activities allow students to interact directly with natural phenomena and secondary data sources. These experiences provide the students with the opportunity to design investigations, collect data, develop manipulative skills, analyse results, collaborate with peers and evaluate and communicate their findings. Experiments can be used to introduce a topic, investigate a phenomenon or allow students to consider and examine questions and curiosities.


Physics guide22

By providing students with the opportunity for hands-on experimentation, they are carrying out some of the same processes that scientists undertake. Experimentation allows students to experience the nature of scientific thought and investigation. All scientific theories and laws begin with observations.

It is important that students are involved in an inquiry-based practical programme that allows for the development of scientific inquiry. It is not enough for students just to be able to follow directions and to simply replicate a given experimental procedure; they must be provided with the opportunities for genuine inquiry. Developing scientific inquiry skills will give students the ability to construct an explanation based on reliable evidence and logical reasoning. Once developed, these higher order thinking skills will enable students to be lifelong learners and scientifically literate.

A school’s practical scheme of work should allow students to experience the full breadth and depth of the course including the option. This practical scheme of work must also prepare students to undertake the independent investigation that is required for the internal assessment. The development of students’ manipulative skills should involve them being able to follow instructions accurately and demonstrate the safe, competent and methodical use of a range of techniques and equipment.

The “Applications and skills” section of the syllabus lists specific lab skills, techniques and experiments that students must experience at some point during their study of the group 4 course. Other recommended lab skills, techniques and experiments are listed in the “Aims” section of the syllabus outline.

Aim 6 of the group 4 subjects directly relates to the development of experimental and investigative skills.

Mathematical requirementsAll Diploma Programme physics students should be able to:

perform the basic arithmetic functions: addition, subtraction, multiplication and division

carry out calculations involving means, decimals, fractions, percentages, ratios, approximations and reciprocals

carry out manipulations with trigonometric functions

carry out manipulations with logarithmic and exponential functions (HL only)

use standard notation (for example, 3.6 × 106)

use direct and inverse proportion

solve simple algebraic equations

solve linear simultaneous equations

plot graphs (with suitable scales and axes) including two variables that show linear and non-linear relationships

interpret graphs, including the significance of gradients, changes in gradients, intercepts and areas

draw lines (either curves or linear) of best fit on a scatter plot graph

on a best-fit linear graph, construct linear lines of maximum and minimum gradients with relative accuracy (by eye) taking into account all uncertainty bars

interpret data presented in various forms (for example, bar charts, histograms and pie charts)

represent arithmetic mean using x-bar notation (for example, x)

express uncertainties to one or two significant figures, with justification.


Physics guide 23

Data bookletThe data booklet must be viewed as an integral part of the physics programme and should be used throughout the delivery of the course and not just reserved for use during the external assessments. The data booklet contains useful equations, constants, data, structural formulae and tables of information. Explicit links have been provided in the “Syllabus outline” section of the subject guide that provide direct references to information in the data booklet which will allow students to become familiar with its use and contents. It is suggested that the data booklet be used for all in-class study and school-based assessments.

For both SL and HL external assessments, clean copies of the data booklet must be made available to both SL and HL candidates for all papers.

Use of information communication technologyThe use of information communication technology (ICT) is encouraged throughout all aspects of the course in relation to both the practical programme and day-to-day classroom activities. Teachers should make use of the ICT pages of the teacher support materials (TSM).

Planning your courseThe syllabus as provided in the subject guide is not intended to be a teaching order. Instead it provides detail of what must be covered by the end of the course. A school should develop a scheme of work that best works for its students. For example, the scheme of work could be developed to match available resources, to take into account student prior learning and experience, or in conjunction with other local requirements.

HL teachers may choose to teach the core and AHL topics at the same time or teach them in a spiral fashion, by teaching the core topics in year one of the course and revisiting the core topics through the delivery of the AHL topics in year two of the course. The option topic could be taught as a stand-alone topic or could be integrated into the teaching of the core and/or AHL topics.

However the course is planned, adequate time must be provided for examination revision. Time must also be given for students to reflect on their learning experience and their growth as learners.


Physics guide24

The IB learner profileThe physics course contributes to the development of the IB learner profile. By following the course, students will have addressed the attributes of the IB learner profile. For example, the requirements of the internal assessment provide opportunities for students to develop every aspect of the profile. For each attribute of the learner profile, a number of references from the group 4 courses are given below.

Learner profile attribute

Biology, chemistry and physics

Inquirers Aims 2 and 6

Practical work and internal assessment

Knowledgeable Aims 1 and 10, international-mindedness links


Thinkers Aims 3 and 4, theory of knowledge links


Communicators Aims 5 and 7, external assessment

Practical work and internal assessment, the group 4 project

Principled Aims 8 and 9

Practical work and internal assessment, ethical behaviour/practice (Ethical practice poster, Animal experimentation policy), academic honesty

Open-minded Aims 8 and 9, international-mindedness links


Caring Aims 8 and 9

Practical work and internal assessment, the group 4 project, ethical behaviour/practice (Ethical practice poster, Animal experimentation policy)

Risk-takers Aims 1 and 6


Balanced Aims 8 and 10

Practical work and internal assessment, the group 4 project and field work

Reflective Aims 5 and 9

Practical work and internal assessment analysis, and group 4 project

Physics guide 2525

Syllabus

Recommended teaching hoursCore 95 hours

Topic 1: Measurements and uncertainties 5

1.1 – Measurements in physics

1.2 – Uncertainties and errors

1.3 – Vectors and scalars

Topic 2: Mechanics 22

2.1 – Motion

2.2 – Forces

2.3 – Work, energy and power

2.4 – Momentum and impulse

Topic 3: Thermal physics 11

3.1 – Thermal concepts

3.2 – Modelling a gas

Topic 4: Waves 15

4.1 – Oscillations

4.2 – Travelling waves

4.3 – Wave characteristics

4.4 – Wave behaviour

4.5 – Standing waves

Topic 5: Electricity and magnetism 15

5.1 – Electric fields

5.2 – Heating effect of electric currents

5.3 – Electric cells

5.4 – Magnetic effects of electric currents

Syllabus content

Syllabus content

Physics guide26

Topic 6: Circular motion and gravitation 5

6.1 – Circular motion

6.2 – Newton’s law of gravitation

Topic 7: Atomic, nuclear and particle physics 14

7.1 – Discrete energy and radioactivity

7.2 – Nuclear reactions

7.3 – The structure of matter

Topic 8: Energy production 8

8.1 – Energy sources

8.2 – Thermal energy transfer

Additional higher level (AHL) 60 hours

Topic 9: Wave phenomena 17

9.1 – Simple harmonic motion

9.2 – Single-slit diffraction

9.3 – Interference

9.4 – Resolution

9.5 – Doppler effect

Topic 10: Fields 11

10.1 – Describing fields

10.2 – Fields at work

Topic 11: Electromagnetic induction 16

11.1 – Electromagnetic induction

11.2 – Power generation and transmission

11.3 – Capacitance

Topic 12: Quantum and nuclear physics 16

12.1 – The interaction of matter with radiation

12.2 – Nuclear physics

Syllabus content

Physics guide 27

Options 15 hours (SL)/25 hours (HL)A: Relativity

Core topicsA.1 – The beginnings of relativity

A.2 – Lorentz transformations

A.3 – Spacetime diagrams

Additional higher level topicsA.4 – Relativistic mechanics (HL only)

A.5 – General relativity (HL only)

B: Engineering physics

Core topicsB.1 – Rigid bodies and rotational dynamics

B.2 – Thermodynamics

Additional higher level topicsB.3 – Fluids and fluid dynamics (HL only)

B.4 – Forced vibrations and resonance (HL only)

Option C: Imaging

Core topicsC.1 – Introduction to imaging

C.2 – Imaging instrumentation

C.3 – Fibre optics

Additional higher level topicsC.4 – Medical imaging (HL only)

Option D: Astrophysics

Core topicsD.1 – Stellar quantities

D.2 – Stellar characteristics and stellar evolution

D.3 – Cosmology

Additional higher level topicsD.4 – Stellar processes (HL only)

D.5 – Further cosmology (HL only)

Physics guide28

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mea

sure

men

t fac

ilita

te th

e sh

arin

g of

kno

wle

dge

in p

hysic

s?

Topi

c 1:

Mea

sure

men

t and

unc

erta

intie

s 5

hour

s

Core

Topic 1: Measurement and uncertainties

Physics guide 29

1.1

– M

easu

rem

ents

in p

hysi

cs

App

licat

ions

and

skill

s:

Usin

g SI

uni

ts in

the

corr

ect f

orm

at fo

r all

requ

ired

mea

sure

men

ts, f

inal

ans

wer

s to

cal

cula

tions

and

pre

sent

atio

n of

raw

and

pro

cess

ed d

ata

Usin

g sc

ient

ific

nota

tion

and

met

ric m

ultip

liers

Quo

ting

and

com

parin

g ra

tios,

valu

es a

nd a

ppro

xim

atio

ns to

the

near

est o

rder

of

mag

nitu

de

Estim

atin

g qu

antit

ies t

o an

app

ropr

iate

num

ber o

f sig

nific

ant f

igur

es

Gui

danc

e:

SI u

nit u

sage

and

info

rmat

ion

can

be fo

und

at th

e w

ebsit

e of

Bur

eau

Inte

rnat

iona

l des

Poi

ds e

t Mes

ures

Stud

ents

will

not

nee

d to

kno

w th

e de

finiti

on o

f SI u

nits

exc

ept w

here

ex

plic

itly

stat

ed in

the

rele

vant

topi

cs in

this

guid

e

Cand

ela

is no

t a re

quire

d SI

uni

t for

this

cour

se

Gui

danc

e on

any

use

of n

on-S

I uni

ts su

ch a

s eV,

MeV

c-2, l

y an

d pc

will

be

prov

ided

in th

e re

leva

nt to

pics

in th

is gu

ide

Furt

her g

uida

nce

on h

ow sc

ient

ific

nota

tion

and

signi

fican

t fig

ures

are

use

d in

ex

amin

atio

ns c

an b

e fo

und

in th

e Te

ache

r sup

port

mat

eria

l

Dat

a bo

okle

t ref

eren

ce:

Met

ric (S

I) m

ultip

liers

can

be

foun

d on

pag

e 5

of th

e ph

ysic

s dat

a bo

okle

t

Uti

lizat

ion:

This

topi

c is

able

to b

e in

tegr

ated

into

any

topi

c ta

ught

at t

he st

art o

f the

co

urse

and

is im

port

ant t

o al

l top

ics

Stud

ents

stud

ying

mor

e th

an o

ne g

roup

4 su

bjec

t will

be

able

to u

se th

ese

skill

s acr

oss a

ll su

bjec

ts

See

Mat

hem

atic

al st

udie

s SL

sub-

topi

cs 1

.2–1

.4

Aim

s: Aim

2 a

nd 3

: thi

s is a

n es

sent

ial a

rea

of k

now

ledg

e th

at a

llow

s sci

entis

ts to

co

llabo

rate

acr

oss t

he g

lobe

Aim

4 a

nd 5

: a c

omm

on a

ppro

ach

to e

xpre

ssin

g re

sults

of a

naly

sis,

eval

uatio

n an

d sy

nthe

sis o

f sci

entif

ic in

form

atio

n en

able

s gre

ater

shar

ing

and

colla

bora

tion


Physics guide30

Esse

ntia

l ide

a: S

cien

tists

aim

tow

ards

des

igni

ng e

xper

imen

ts th

at c

an g

ive

a “t

rue

valu

e” fr

om th

eir m

easu

rem

ents

, but

due

to th

e lim

ited

prec

ision

in m

easu

ring

devi

ces,

they

oft

en q

uote

thei

r res

ults

with

som

e fo

rm o

f unc

erta

inty

.

1.2

– U

ncer

tain

ties

and

err

ors

Nat

ure

of sc

ienc

e:

Unc

erta

intie

s: “A

ll sc

ient

ific

know

ledg

e is

unce

rtai

n… if

you

hav

e m

ade

up y

our m

ind

alre

ady,

you

mig

ht n

ot so

lve

it. W

hen

the

scie

ntis

t tel

ls yo

u he

doe

s not

kno

w th

e an

swer

, he

is an

igno

rant

man

. Whe

n he

tells

you

he

has a

hun

ch a

bout

how

it is

goi

ng to

wor

k, h

e is

unce

rtai

n ab

out i

t. W

hen

he is

pre

tty

sure

of h

ow it

is g

oing

to w

ork,

an

d he

tells

you

, ‘Th

is is

the

way

it’s

goin

g to

wor

k, I’

ll be

t,’ h

e st

ill is

in so

me

doub

t. An

d it

is of

par

amou

nt im

port

ance

, in

orde

r to

mak

e pr

ogre

ss, t

hat w

e re

cogn

ize

this

igno

ranc

e an

d th

is do

ubt.

Beca

use

we

have

the

doub

t, w

e th

en p

ropo

se lo

okin

g in

new

dire

ctio

ns fo

r new

idea

s.” (3

.4)

Feyn

man

, Ric

hard

P. 1

998.

The

Mea

ning

of I

t All:

Tho

ught

s of a

Citi

zen-

Scie

ntist

. Rea

ding

, Mas

sach

uset

ts, U

SA. P

erse

us. P

13.

Und

erst

andi

ngs:

Rand

om a

nd sy

stem

atic

err

ors

Abso

lute

, fra

ctio

nal a

nd p

erce

ntag

e un

cert

aint

ies

Erro

r bar

s

Unc

erta

inty

of g

radi

ent a

nd in

terc

epts

App

licat

ions

and

skill

s:

Expl

aini

ng h

ow ra

ndom

and

syst

emat

ic e

rror

s can

be

iden

tifie

d an

d re

duce

d

Colle

ctin

g da

ta th

at in

clud

e ab

solu

te a

nd/o

r fra

ctio

nal u

ncer

tain

ties

and

stat

ing

thes

e as

an

unce

rtai

nty

rang

e (e

xpre

ssed

as:

best

est

imat

e ±

unce

rtai

nty

rang

e)

Prop

agat

ing

unce

rtai

ntie

s thr

ough

cal

cula

tions

invo

lvin

g ad

ditio

n,

subt

ract

ion,

mul

tiplic

atio

n, d

ivisi

on a

nd ra

ising

to a

pow

er

Det

erm

inin

g th

e un

cert

aint

y in

gra

dien

ts a

nd in

terc

epts

Theo

ry o

f kno

wle

dge:

“One

aim

of t

he p

hysic

al sc

ienc

es h

as b

een

to g

ive

an e

xact

pic

ture

of t

he

mat

eria

l wor

ld. O

ne a

chie

vem

ent o

f phy

sics i

n th

e tw

entie

th c

entu

ry h

as b

een

to p

rove

that

this

aim

is u

natt

aina

ble.

” – Ja

cob

Bron

owsk

i. Ca

n sc

ient

ists

eve

r be

trul

y ce

rtai

n of

thei

r disc

over

ies?

Uti

lizat

ion:

Stud

ents

stud

ying

mor

e th

an o

ne g

roup

4 su

bjec

t will

be

able

to u

se th

ese

skill

s acr

oss a

ll su

bjec

ts


Physics guide 31

1.2

– U

ncer

tain

ties

and

err

ors

Gui

danc

e:

Anal

ysis

of u

ncer

tain

ties w

ill n

ot b

e ex

pect

ed fo

r trig

onom

etric

or l

ogar

ithm

ic

func

tions

in e

xam

inat

ions

Furt

her g

uida

nce

on h

ow u

ncer

tain

ties,

erro

r bar

s and

line

s of b

est f

it ar

e us

ed

in e

xam

inat

ions

can

be

foun

d in

the

Teac

her s

uppo

rt m

ater

ial

Dat

a bo

okle

t ref

eren

ce:

If y

ab

=±

then

y

ab

∆=

∆+

∆

If y

ab c=

then

y y

a ab b

c c∆

=∆

+∆

+∆

If y

an=

th

en

y yn

a a∆

=∆

Aim

s: Aim

4: i

t is i

mpo

rtan

t tha

t stu

dent

s see

scie

ntifi

c er

rors

and

unc

erta

intie

s not

on

ly a

s the

rang

e of

pos

sible

ans

wer

s but

as a

n in

tegr

al p

art o

f the

scie

ntifi

c pr

oces

s

Aim

9: t

he p

roce

ss o

f usin

g un

cert

aint

ies i

n cl

assic

al p

hysic

s can

be

com

pare

d to

the

view

of u

ncer

tain

ties i

n m

oder

n (a

nd p

artic

ular

ly q

uant

um) p

hysic

s

Topic 1: Measurem

ent and uncertainties

Physics guide32 Essential idea: Some quantities have direction and magnitude, others have magnitude only, and this understanding is the key to correct manipulation of quantities. This sub-

topic will have broad applications across multiple fields within physics and other sciences.

1.3 – Vectors and scalars

Nature of science:

Models: First mentioned explicitly in a scientific paper in 1846, scalars and vectors reflected the work of scientists and mathematicians across the globe for over 300 years on representing measurements in three-dimensional space. (1.10)

Understandings:

Vector and scalar quantities

Combination and resolution of vectors


Solving vector problems graphically and algebraically

Guidance:

Resolution of vectors will be limited to two perpendicular directions

Problems will be limited to addition and subtraction of vectors and the multiplication and division of vectors by scalars


Vector notation forms the basis of mapping across the globe


What is the nature of certainty and proof in mathematics?

Utilization:

Navigation and surveying (see Geography SL/HL syllabus: Geographic skills)

Force and field strength (see Physics sub-topics 2.2, 5.1, 6.1 and 10.1)

Vectors (see Mathematics HL sub-topic 4.1; Mathematics SL sub-topic 4.1)


Physics guide 33

1.3

– Ve

ctor

s and

scal

ars

Dat

a bo

okle

t ref

eren

ce:

AV

AH

θ

A

AA

cos

Hθ

=

AA

sinv

θ=

Aim

s: Aim

2 a

nd 3

: thi

s is a

fund

amen

tal a

spec

t of s

cien

tific

lang

uage

that

allo

ws f

or

spat

ial r

epre

sent

atio

n an

d m

anip

ulat

ion

of a

bstr

act c

once

pts

Core

Physics guide34

Esse

ntia

l ide

a: M

otio

n m

ay b

e de

scrib

ed a

nd a

naly

sed

by th

e us

e of

gra

phs a

nd e

quat

ions

.

2.1

– M

otio

n

Nat

ure

of sc

ienc

e:

Obs

erva

tions

: The

idea

s of m

otio

n ar

e fu

ndam

enta

l to

man

y ar

eas o

f phy

sics,

prov

idin

g a

link

to th

e co

nsid

erat

ion

of fo

rces

and

thei

r im

plic

atio

n. T

he k

inem

atic

equ

atio

ns

for u

nifo

rm a

ccel

erat

ion

wer

e de

velo

ped

thro

ugh

care

ful o

bser

vatio

ns o

f the

nat

ural

wor

ld. (

1.8)

Und

erst

andi

ngs:

Dis

tanc

e an

d di

spla

cem

ent

Spee

d an

d ve

loci

ty

Acce

lera

tion

Gra

phs d

escr

ibin

g m

otio

n

Equa

tions

of m

otio

n fo

r uni

form

acc

eler

atio

n

Proj

ectil

e m

otio

n

Flui

d re

sista

nce

and

term

inal

spee

d

App

licat

ions

and

skill

s:

Det

erm

inin

g in

stan

tane

ous a

nd a

vera

ge v

alue

s for

vel

ocity

, spe

ed a

nd

acce

lera

tion

Solv

ing

prob

lem

s usin

g eq

uatio

ns o

f mot

ion

for u

nifo

rm a

ccel

erat

ion

Sket

chin

g an

d in

terp

retin

g m

otio

n gr

aphs

Det

erm

inin

g th

e ac

cele

ratio

n of

free

-fall

expe

rimen

tally

Anal

ysin

g pr

ojec

tile

mot

ion,

incl

udin

g th

e re

solu

tion

of v

ertic

al a

nd h

oriz

onta

l co

mpo

nent

s of a

ccel

erat

ion,

vel

ocity

and

disp

lace

men

t

Qua

litat

ivel

y de

scrib

ing

the

effe

ct o

f flu

id re

sista

nce

on fa

lling

obj

ects

or

proj

ectil

es, i

nclu

ding

reac

hing

term

inal

spee

d

Inte

rnat

iona

l-min

dedn

ess:

Inte

rnat

iona

l coo

pera

tion

is ne

eded

for t

rack

ing

ship

ping

, lan

d-ba

sed

tran

spor

t, ai

rcra

ft a

nd o

bjec

ts in

spac

e

Theo

ry o

f kno

wle

dge:

The

inde

pend

ence

of h

oriz

onta

l and

ver

tical

mot

ion

in p

roje

ctile

mot

ion

seem

s to

be c

ount

er-in

tuiti

ve. H

ow d

o sc

ient

ists

wor

k ar

ound

thei

r int

uitio

ns?

How

do

scie

ntis

ts m

ake

use

of th

eir i

ntui

tions

?

Uti

lizat

ion:

Div

ing,

par

achu

ting

and

simila

r act

iviti

es w

here

flui

d re

sista

nce

affe

cts m

otio

n

The

accu

rate

use

of b

allis

tics r

equi

res c

aref

ul a

naly

sis

Biom

echa

nics

(see

Spo

rts,

exer

cise

and

hea

lth sc

ienc

e SL

sub-

topi

c 4.

3)

Qua

drat

ic fu

nctio

ns (s

ee M

athe

mat

ics H

L sub

-top

ic 2

.6; M

athe

mat

ics S

L

sub-

topi

c 2.

4; M

athe

mat

ical

stud

ies S

L su

b-to

pic

6.3)

The

kine

mat

ic e

quat

ions

are

trea

ted

in c

alcu

lus f

orm

in M

athe

mat

ics H

L

sub-

topi

c 6.

6 an

d M

athe

mat

ics S

L su

b-to

pic

6.6

Topi

c 2:

Mec

hani

cs

22 h

ours

Core

Topic 2: Mechanics

Physics guide 35

2.1

– M

otio

n

Gui

danc

e:

Calc

ulat

ions

will

be

rest

ricte

d to

thos

e ne

glec

ting

air r

esis

tanc

e

Proj

ectil

e m

otio

n w

ill o

nly

invo

lve

prob

lem

s usin

g a

cons

tant

val

ue o

f g c

lose

to

the

surf

ace

of th

e Ea

rth

The

equa

tion

of th

e pa

th o

f a p

roje

ctile

will

not

be

requ

ired

Dat

a bo

okle

t ref

eren

ce:

vu

at=

+

sut

at1 2

2=

+

vu

as22

2=

+

sv

ut

2(

)=

+

Aim

s: Aim

2: m

uch

of th

e de

velo

pmen

t of c

lass

ical

phy

sics h

as b

een

built

on

the

adva

nces

in k

inem

atic

s

Aim

6: e

xper

imen

ts, i

nclu

ding

use

of d

ata

logg

ing,

cou

ld in

clud

e (b

ut a

re

not l

imite

d to

): de

term

inat

ion

of g

, est

imat

ing

spee

d us

ing

trav

el ti

met

able

s, an

alys

ing

proj

ectil

e m

otio

n, a

nd in

vest

igat

ing

mot

ion

thro

ugh

a flu

id

Aim

7: t

echn

olog

y ha

s allo

wed

for m

ore

accu

rate

and

pre

cise

mea

sure

men

ts

of m

otio

n, in

clud

ing

vide

o an

alys

is of

real

-life

pro

ject

iles a

nd m

odel

ling/

simul

atio

ns o

f ter

min

al v

eloc

ity

Topic 2: Mechanics

Physics guide36

Esse

ntia

l ide

a: C

lass

ical

phy

sics r

equi

res a

forc

e to

cha

nge

a st

ate

of m

otio

n, a

s sug

gest

ed b

y N

ewto

n in

his

law

s of m

otio

n.

2.2

– Fo

rces

Nat

ure

of sc

ienc

e:

Usin

g m

athe

mat

ics:

Isaa

c N

ewto

n pr

ovid

ed th

e ba

sis fo

r muc

h of

our

und

erst

andi

ng o

f for

ces a

nd m

otio

n by

form

aliz

ing

the

prev

ious

wor

k of

scie

ntis

ts th

roug

h th

e ap

plic

atio

n of

mat

hem

atic

s by

inve

ntin

g ca

lcul

us to

ass

ist w

ith th

is. (

2.4)

Intu

ition

: The

tale

of t

he fa

lling

app

le d

escr

ibes

sim

ply

one

of th

e m

any

flash

es o

f int

uitio

n th

at w

ent i

nto

the

publ

icat

ion

of P

hilo

soph

iæ N

atur

alis

Prin

cipi

a M

athe

mat

ica

in

1687

. (1.

5)

Und

erst

andi

ngs:

Obj

ects

as p

oint

par

ticle

s

Free

-bod

y di

agra

ms

Tran

slatio

nal e

quili

briu

m

New

ton’

s law

s of m

otio

n

Solid

fric

tion

App

licat

ions

and

skill

s:

Repr

esen

ting

forc

es a

s vec

tors

Sket

chin

g an

d in

terp

retin

g fre

e-bo

dy d

iagr

ams

Des

crib

ing

the

cons

eque

nces

of N

ewto

n’s f

irst l

aw fo

r tra

nsla

tiona

l eq

uilib

rium

Usin

g N

ewto

n’s s

econ

d la

w q

uant

itativ

ely

and

qual

itativ

ely

Iden

tifyi

ng fo

rce

pairs

in th

e co

ntex

t of N

ewto

n’s t

hird

law

Solv

ing

prob

lem

s inv

olvi

ng fo

rces

and

det

erm

inin

g re

sulta

nt fo

rce

Des

crib

ing

solid

fric

tion

(sta

tic a

nd d

ynam

ic) b

y co

effic

ient

s of f

rictio

n

Theo

ry o

f kno

wle

dge:

Clas

sical

phy

sics b

elie

ved

that

the

who

le o

f the

futu

re o

f the

uni

vers

e co

uld

be p

redi

cted

from

kno

wle

dge

of th

e pr

esen

t sta

te. T

o w

hat e

xten

t can

kn

owle

dge

of th

e pr

esen

t giv

e us

kno

wle

dge

of th

e fu

ture

?

Uti

lizat

ion:

Mot

ion

of c

harg

ed p

artic

les i

n fie

lds (

see

Phys

ics s

ub-t

opic

s 5.4

, 6.1,

11.1,

12.2

)

Appl

icat

ion

of fr

ictio

n in

circ

ular

mot

ion

(see

Phy

sics s

ub-t

opic

6.1)

Cons

truc

tion

(con

sider

ing

anci

ent a

nd m

oder

n ap

proa

ches

to sa

fety

, lo

ngev

ity a

nd c

onsid

erat

ion

of lo

cal w

eath

er a

nd g

eolo

gica

l inf

luen

ces)

Biom

echa

nics

(see

Spo

rts,

exer

cise

and

hea

lth sc

ienc

e SL

sub-

topi

c 4.

3)

Topic 2: Mechanics

Physics guide 37

2.2

– Fo

rces

Gui

danc

e:

Stud

ents

shou

ld la

bel f

orce

s usin

g co

mm

only

acc

epte

d na

mes

or s

ymbo

ls (fo

r ex

ampl

e: w

eigh

t or f

orce

of g

ravi

ty o

r mg)

Free

-bod

y di

agra

ms s

houl

d sh

ow sc

aled

vec

tor l

engt

hs a

ctin

g fro

m th

e po

int

of a

pplic

atio

n

Exam

ples

and

que

stio

ns w

ill b

e lim

ited

to c

onst

ant m

ass

mg

shou

ld b

e id

entif

ied

as w

eigh

t

Calc

ulat

ions

rela

ting

to th

e de

term

inat

ion

of re

sulta

nt fo

rces

will

be

rest

ricte

d to

one

- and

two-

dim

ensio

nal s

ituat

ions

Dat

a bo

okle

t ref

eren

ce:

Fm

a=

FR

fsµ

≤

FR

fdµ

≤

Aim

s: Aim

s 2 a

nd 3

: New

ton’

s wor

k is

ofte

n de

scrib

ed b

y th

e qu

ote

from

a le

tter

he

wro

te to

his

rival

, Rob

ert H

ooke

, 11

year

s bef

ore

the

publ

icat

ion

of P

hilo

soph

iæ

Nat

ural

is Pr

inci

pia

Mat

hem

atic

a, w

hich

stat

es: “

Wha

t Des

cart

es d

id w

as a

goo

d st

ep. Y

ou h

ave

adde

d m

uch

seve

ral w

ays,

and

espe

cial

ly in

taki

ng th

e co

lour

s of

thin

pla

tes i

nto

philo

soph

ical

cons

ider

atio

n. If

I hav

e se

en a

litt

le fu

rthe

r it i

s by

stan

ding

on

the

shou

lder

s of G

iant

s.” It

shou

ld b

e re

mem

bere

d th

at th

is qu

ote

is al

so in

spire

d, th

is tim

e by

writ

ers w

ho h

ad b

een

usin

g ve

rsio

ns o

f it f

or a

t lea

st

500

year

s bef

ore

New

ton’

s tim

e.

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

verif

icat

ion

of

New

ton’

s sec

ond

law

; inv

estig

atin

g fo

rces

in e

quili

briu

m; d

eter

min

atio

n of

the

effe

cts o

f fric

tion

Topic 2: Mechanics

Physics guide38

Esse

ntia

l ide

a: T

he fu

ndam

enta

l con

cept

of e

nerg

y la

ys th

e ba

sis u

pon

whi

ch m

uch

of sc

ienc

e is

built

.

2.3

– W

ork,

ene

rgy

and

pow

er

Nat

ure

of sc

ienc

e:

Theo

ries:

Man

y ph

enom

ena

can

be fu

ndam

enta

lly u

nder

stoo

d th

roug

h ap

plic

atio

n of

the

theo

ry o

f con

serv

atio

n of

ene

rgy.

Ove

r tim

e, sc

ient

ists

hav

e ut

ilize

d th

is th

eory

bo

th to

exp

lain

nat

ural

phe

nom

ena

and,

mor

e im

port

antly

, to

pred

ict t

he o

utco

me

of p

revi

ousl

y un

know

n in

tera

ctio

ns. T

he c

once

pt o

f ene

rgy

has e

volv

ed a

s a re

sult

of

reco

gniti

on o

f the

rela

tions

hip

betw

een

mas

s and

ene

rgy.

(2.2

)

Und

erst

andi

ngs:

Kine

tic e

nerg

y

Gra

vita

tiona

l pot

entia

l ene

rgy

Elas

tic p

oten

tial e

nerg

y

Wor

k do

ne a

s ene

rgy

tran

sfer

Pow

er a

s rat

e of

ene

rgy

tran

sfer

Prin

cipl

e of

con

serv

atio

n of

ene

rgy

Effic

ienc

y

App

licat

ions

and

skill

s:

Disc

ussin

g th

e co

nser

vatio

n of

tota

l ene

rgy

with

in e

nerg

y tr

ansf

orm

atio

ns

Sket

chin

g an

d in

terp

retin

g fo

rce–

dist

ance

gra

phs

Det

erm

inin

g w

ork

done

incl

udin

g ca

ses w

here

a re

sistiv

e fo

rce

acts

Solv

ing

prob

lem

s inv

olvi

ng p

ower

Qua

ntita

tivel

y de

scrib

ing

effic

ienc

y in

ene

rgy

tran

sfer

s

Gui

danc

e:

Case

s whe

re th

e lin

e of

act

ion

of th

e fo

rce

and

the

disp

lace

men

t are

not

pa

ralle

l sho

uld

be c

onsid

ered

Exam

ples

shou

ld in

clud

e fo

rce–

dist

ance

gra

phs f

or v

aria

ble

forc

es

Theo

ry o

f kno

wle

dge:

To w

hat e

xten

t is s

cien

tific

kno

wle

dge

base

d on

fund

amen

tal c

once

pts s

uch

as e

nerg

y? W

hat h

appe

ns to

scie

ntifi

c kn

owle

dge

whe

n ou

r und

erst

andi

ng o

f su

ch fu

ndam

enta

l con

cept

s cha

nges

or e

volv

es?

Uti

lizat

ion:

Ener

gy is

als

o co

vere

d in

oth

er g

roup

4 su

bjec

ts (f

or e

xam

ple,

see:

Bio

logy

to

pics

2, 4

and

8; C

hem

istry

topi

cs 5

, 15,

and

C; S

port

s, ex

erci

se a

nd h

ealth

sc

ienc

e to

pics

3, A

.2, C

.3 a

nd D

.3; E

nviro

nmen

tal s

yste

ms a

nd so

ciet

ies t

opic

s 1,

2, a

nd 3

)

Ener

gy c

onve

rsio

ns a

re e

ssen

tial f

or e

lect

rical

ene

rgy

gene

ratio

n (s

ee P

hysic

s to

pic

5 an

d su

b-to

pic

8.1)

Ener

gy c

hang

es o

ccur

ring

in si

mpl

e ha

rmon

ic m

otio

n (s

ee P

hysic

s sub

-top

ics

4.1

and

9.1)

Topic 2: Mechanics

Physics guide 39

2.3

– W

ork,

ene

rgy

and

pow

er

Dat

a bo

okle

t ref

eren

ce:

WFs

cosθ

=

Em

v1 2

K2

= =∆

Ek

x1 2

P2

Em

gh

P∆

=∆ Fv

pow

er=

Effic

ienc

y=

usef

ulw

ork

out

tota

lwor

kin

=us

eful

pow

erou

tto

talp

ower

in

Aim

s: Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

rela

tions

hip

of

kine

tic a

nd g

ravi

tatio

nal p

oten

tial e

nerg

y fo

r a fa

lling

mas

s; po

wer

and

ef

ficie

ncy

of m

echa

nica

l obj

ects

; com

paris

on o

f diff

eren

t situ

atio

ns in

volv

ing

elas

tic p

oten

tial e

nerg

y

Aim

8: b

y lin

king

this

sub-

topi

c w

ith to

pic

8, st

uden

ts sh

ould

be

awar

e of

th

e im

port

ance

of e

ffic

ienc

y an

d its

impa

ct o

f con

serv

ing

the

fuel

use

d fo

r en

ergy

pro

duct

ion

Topic 2: Mechanics

Physics guide40

Esse

ntia

l ide

a: C

onse

rvat

ion

of m

omen

tum

is a

n ex

ampl

e of

a la

w th

at is

nev

er v

iola

ted.

2.4

– M

omen

tum

and

impu

lse

Nat

ure

of sc

ienc

e:

The

conc

ept o

f mom

entu

m a

nd th

e pr

inci

ple

of m

omen

tum

con

serv

atio

n ca

n be

use

d to

ana

lyse

and

pre

dict

the

outc

ome

of a

wid

e ra

nge

of p

hysic

al in

tera

ctio

ns, f

rom

m

acro

scop

ic m

otio

n to

mic

rosc

opic

col

lisio

ns. (

1.9)

Und

erst

andi

ngs:

New

ton’

s sec

ond

law

exp

ress

ed in

term

s of r

ate

of c

hang

e of

mom

entu

m

Impu

lse

and

forc

e–tim

e gr

aphs

Cons

erva

tion

of li

near

mom

entu

m

Elas

tic c

ollis

ions

, ine

last

ic c

ollis

ions

and

exp

losio

ns

App

licat

ions

and

skill

s:

Appl

ying

cons

erva

tion

of m

omen

tum

in si

mpl

e iso

late

d sy

stem

s inc

ludi

ng (b

ut

not l

imite

d to

) col

lisio

ns, e

xplo

sions

, or w

ater

jets

Usin

g N

ewto

n’s s

econ

d la

w q

uant

itativ

ely

and

qual

itativ

ely

in c

ases

whe

re

mas

s is n

ot c

onst

ant

Sket

chin

g an

d in

terp

retin

g fo

rce–

time

grap

hs

Det

erm

inin

g im

puls

e in

var

ious

con

text

s inc

ludi

ng (b

ut n

ot li

mite

d to

) car

sa

fety

and

spor

ts

Qua

litat

ivel

y an

d qu

antit

ativ

ely

com

parin

g sit

uatio

ns in

volv

ing

elas

tic

colli

sions

, ine

last

ic c

ollis

ions

and

exp

losio

ns

Inte

rnat

iona

l-min

dedn

ess:

Auto

mob

ile p

assiv

e sa

fety

stan

dard

s hav

e be

en a

dopt

ed a

cros

s the

glo

be

base

d on

rese

arch

con

duct

ed in

man

y co

untr

ies

Theo

ry o

f kno

wle

dge:

Do

cons

erva

tion

law

s res

tric

t or e

nabl

e fu

rthe

r dev

elop

men

t in

phys

ics?

Uti

lizat

ion:

Jet e

ngin

es a

nd ro

cket

s

Mar

tial

art

s

Part

icle

theo

ry a

nd c

ollis

ions

(see

Phy

sics s

ub-t

opic

3.1)

Topic 2: Mechanics

Physics guide 41

2.4

– M

omen

tum

and

impu

lse

Gui

danc

e:

Stud

ents

shou

ld b

e aw

are

that

F =

ma

is eq

uiva

lent

of

Fp t

=∆ ∆

onl

y w

hen

mas

s is

cons

tant

Solv

ing

simul

tane

ous e

quat

ions

invo

lvin

g co

nser

vatio

n of

mom

entu

m a

nd

ener

gy in

col

lisio

ns w

ill n

ot b

e re

quire

d

Calc

ulat

ions

rela

ting

to c

ollis

ions

and

exp

losio

ns w

ill b

e re

stric

ted

to o

ne-

dim

ensio

nal s

ituat

ions

A co

mpa

rison

bet

wee

n en

ergy

invo

lved

in in

elas

tic c

ollis

ions

(in

whi

ch k

inet

ic

ener

gy is

not

con

serv

ed) a

nd th

e co

nser

vatio

n of

(tot

al) e

nerg

y sh

ould

be

mad

e

Dat

a bo

okle

t ref

eren

ce:

pm

v=

Fp t

=∆ ∆

Ep m2

K

2

=

Ft

pIm

pulse

=∆

=∆

Aim

s: Aim

3: c

onse

rvat

ion

law

s in

scie

nce

disc

iplin

es h

ave

play

ed a

maj

or ro

le in

ou

tlini

ng th

e lim

its w

ithin

whi

ch sc

ient

ific

theo

ries a

re d

evel

oped

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

anal

ysis

of

colli

sions

with

resp

ect t

o en

ergy

tran

sfer

; im

puls

e in

vest

igat

ions

to

dete

rmin

e ve

loci

ty, f

orce

, tim

e, o

r mas

s; de

term

inat

ion

of a

mou

nt o

f tr

ansf

orm

ed e

nerg

y in

inel

astic

col

lisio

ns

Aim

7: t

echn

olog

y ha

s allo

wed

for m

ore

accu

rate

and

pre

cise

mea

sure

men

ts

of fo

rce

and

mom

entu

m, i

nclu

ding

vid

eo a

naly

sis o

f rea

l-life

col

lisio

ns a

nd

mod

ellin

g/sim

ulat

ions

of m

olec

ular

col

lisio

ns

Physics guide42

Essential idea: Thermal physics deftly demonstrates the links between the macroscopic measurements essential to many scientific models with the microscopic properties that underlie these models.


Nature of science:

Evidence through experimentation: Scientists from the 17th and 18th centuries were working without the knowledge of atomic structure and sometimes developed theories that were later found to be incorrect, such as phlogiston and perpetual motion capabilities. Our current understanding relies on statistical mechanics providing a basis for our use and understanding of energy transfer in science. (1.8)

Understandings:

Molecular theory of solids, liquids and gasesTemperature and absolute temperatureInternal energySpecific heat capacityPhase changeSpecific latent heat


Describing temperature change in terms of internal energy

Using Kelvin and Celsius temperature scales and converting between them

Applying the calorimetric techniques of specific heat capacity or specific latent heat experimentally

Describing phase change in terms of molecular behaviour

Sketching and interpreting phase change graphs

Calculating energy changes involving specific heat capacity and specific latent heat of fusion and vaporization


The topic of thermal physics is a good example of the use of international systems of measurement that allow scientists to collaborate effectively


Observation through sense perception plays a key role in making measurements. Does sense perception play different roles in different areas of knowledge?

Utilization:

Pressure gauges, barometers and manometers are a good way to present aspects of this sub-topic

Higher level students, especially those studying option B, can be shown links to thermodynamics (see Physics topic 9 and option sub-topic B.4)

Particulate nature of matter (see Chemistry sub-topic 1.3) and measuring energy changes (see Chemistry sub-topic 5.1)

Water (see Biology sub-topic 2.2)

Topic 3: Thermal physics 11 hours

Core

Topic 3: Thermal physics

Physics guide43


Guidance:

Internal energy is taken to be the total intermolecular potential energy + the total random kinetic energy of the molecules

Phase change graphs may have axes of temperature versus time or temperature versus energy

The effects of cooling should be understood qualitatively but cooling correction calculations are not required


Q mc T= ∆

Q mL=

Aims:

Aim 3: an understanding of thermal concepts is a fundamental aspect of many areas of science

Aim 6: experiments could include (but are not limited to): transfer of energy due to temperature difference; calorimetric investigations; energy involved in phase changes

Topic 3: Thermal physics

Physics guide44 Essential idea: The properties of ideal gases allow scientists to make predictions of the behaviour of real gases.


Nature of science:

Collaboration: Scientists in the 19th century made valuable progress on the modern theories that form the basis of thermodynamics, making important links with other sciences, especially chemistry. The scientific method was in evidence with contrasting but complementary statements of some laws derived by different scientists. Empirical and theoretical thinking both have their place in science and this is evident in the comparison between the unattainable ideal gas and real gases. (4.1)

Understandings:

Pressure

Equation of state for an ideal gas

Kinetic model of an ideal gas

Mole, molar mass and the Avogadro constant

Differences between real and ideal gases


Solving problems using the equation of state for an ideal gas and gas laws

Sketching and interpreting changes of state of an ideal gas on pressure–volume, pressure–temperature and volume–temperature diagrams

Investigating at least one gas law experimentally

Guidance:

Students should be aware of the assumptions that underpin the molecular kinetic theory of ideal gases

Gas laws are limited to constant volume, constant temperature, constant pressure and the ideal gas law

Students should understand that a real gas approximates to an ideal gas at conditions of low pressure, moderate temperature and low density


When does modelling of “ideal” situations become “good enough” to count as knowledge?

Utilization:

Transport of gases in liquid form or at high pressures/densities is common practice across the globe. Behaviour of real gases under extreme conditions needs to be carefully considered in these situations.

Consideration of thermodynamic processes is essential to many areas of chemistry (see Chemistry sub-topic 1.3)

Respiration processes (see Biology sub-topic D.6)

Aims:

Aim 3: this is a good topic to make comparisons between empirical and theoretical thinking in science

Aim 6: experiments could include (but are not limited to): verification of gas laws; calculation of the Avogadro constant; virtual investigation of gas law parameters not possible within a school laboratory setting

Topic 3: Therm

al physics

Physics guide45



pFA

=

nN

NA

=

pV nRT=

E k T RN

T32

32K B

A

= =

Physics guide46

Esse

ntia

l ide

a: A

stu

dy o

f osc

illat

ions

und

erpi

ns m

any

area

s of

phy

sics

wit

h si

mpl

e ha

rmon

ic m

otio

n (s

hm),

a fu

ndam

enta

l osc

illat

ion

that

app

ears

in v

ario

us

natu

ral p

heno

men

a.

4.1

– O

scill

atio

ns

Nat

ure

of sc

ienc

e:

Mod

els:

Osc

illat

ions

pla

y a

grea

t par

t in

our l

ives

, fro

m th

e tid

es to

the

mot

ion

of th

e sw

ingi

ng p

endu

lum

that

onc

e go

vern

ed o

ur p

erce

ptio

n of

tim

e. G

ener

al p

rinci

ples

go

vern

this

area

of p

hysic

s, fro

m w

ater

wav

es in

the

deep

oce

an o

r the

osc

illat

ions

of a

car

susp

ensio

n sy

stem

. Thi

s int

rodu

ctio

n to

the

topi

c re

min

ds u

s tha

t not

all

osci

llatio

ns a

re is

ochr

onou

s. H

owev

er, t

he si

mpl

e ha

rmon

ic o

scill

ator

is o

f gre

at im

port

ance

to p

hysic

ists

bec

ause

all

perio

dic

osci

llatio

ns c

an b

e de

scrib

ed th

roug

h th

e m

athe

mat

ics o

f sim

ple

harm

onic

mot

ion.

(1.10

)

Und

erst

andi

ngs:

Sim

ple

harm

onic

osc

illat

ions

Tim

e pe

riod,

freq

uenc

y, a

mpl

itude

, disp

lace

men

t and

pha

se d

iffer

ence

Cond

ition

s for

sim

ple

harm

onic

mot

ion

App

licat

ions

and

skill

s:

Qua

litat

ivel

y de

scrib

ing

the

ener

gy c

hang

es ta

king

pla

ce d

urin

g on

e cy

cle

of

an o

scill

atio

n

Sket

chin

g an

d in

terp

retin

g gr

aphs

of s

impl

e ha

rmon

ic m

otio

n ex

ampl

es

Inte

rnat

iona

l-min

dedn

ess:

Osc

illat

ions

are

use

d to

def

ine

the

time

syst

ems o

n w

hich

nat

ions

agr

ee so

th

at th

e w

orld

can

be

kept

in sy

nchr

oniz

atio

n. T

his i

mpa

cts m

ost a

reas

of o

ur

lives

incl

udin

g th

e pr

ovisi

on o

f ele

ctric

ity, t

rave

l and

loca

tion-

dete

rmin

ing

devi

ces a

nd a

ll m

icro

elec

tron

ics.

Theo

ry o

f kno

wle

dge:

The

harm

onic

osc

illat

or is

a p

arad

igm

for m

odel

ling

whe

re a

sim

ple

equa

tion

is us

ed to

des

crib

e a

com

plex

phe

nom

enon

. How

do

scie

ntis

ts k

now

whe

n a

simpl

e m

odel

is n

ot d

etai

led

enou

gh fo

r the

ir re

quire

men

ts?

Topi

c 4:

Wav

es

15 h

ours

Core

Topic 4: Waves

Physics guide 47

4.1

– O

scill

atio

ns

Gui

danc

e:

Gra

phs d

escr

ibin

g sim

ple

harm

onic

mot

ion

shou

ld in

clud

e di

spla

cem

ent–

time,

vel

ocity

–tim

e, a

ccel

erat

ion–

time

and

acce

lera

tion–

disp

lace

men

t

Stud

ents

are

exp

ecte

d to

und

erst

and

the

signi

fican

ce o

f the

neg

ativ

e sig

n in

th

e re

latio

nshi

p: a

x∝

−D

ata

book

let r

efer

ence

:

Tf1

=

Uti

lizat

ion:

Isoc

hron

ous o

scill

atio

ns c

an b

e us

ed to

mea

sure

tim

e

Man

y sy

stem

s can

app

roxi

mat

e sim

ple

harm

onic

mot

ion:

mas

s on

a sp

ring,

flu

id in

U-t

ube,

mod

els o

f ice

berg

s osc

illat

ing

vert

ical

ly in

the

ocea

n, a

nd

mot

ion

of a

sphe

re ro

lling

in a

con

cave

mirr

or

Sim

ple

harm

onic

mot

ion

is fre

quen

tly fo

und

in th

e co

ntex

t of m

echa

nics

(see

Ph

ysic

s top

ic 2

)

Aim

s: Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

mas

s on

a sp

ring;

sim

ple

pend

ulum

; mot

ion

on a

cur

ved

air t

rack

Aim

7: I

T sk

ills c

an b

e us

ed to

mod

el th

e sim

ple

harm

onic

mot

ion

defin

ing

equa

tion;

this

give

s val

uabl

e in

sight

into

the

mea

ning

of t

he e

quat

ion

itsel

f

Topic 4: Waves

Physics guide48

Esse

ntia

l ide

a: T

here

are

man

y fo

rms

of w

aves

ava

ilabl

e to

be

stud

ied.

A c

omm

on c

hara

cter

istic

of a

ll tr

avel

ling

wav

es is

that

they

car

ry e

nerg

y, b

ut g

ener

ally

the

med

ium

th

roug

h w

hich

they

trav

el w

ill n

ot b

e pe

rman

ently

dis

turb

ed.

4.2

– Tr

avel

ling

wav

es

Nat

ure

of sc

ienc

e:

Patt

erns

, tre

nds a

nd d

iscre

panc

ies:

Scie

ntis

ts h

ave

disc

over

ed c

omm

on fe

atur

es o

f wav

e m

otio

n th

roug

h ca

refu

l obs

erva

tions

of t

he n

atur

al w

orld

, loo

king

for p

atte

rns,

tren

ds a

nd d

iscre

panc

ies a

nd a

skin

g fu

rthe

r que

stio

ns b

ased

on

thes

e fin

ding

s. (3

.1)

Und

erst

andi

ngs:

Trav

ellin

g w

aves

Wav

elen

gth,

freq

uenc

y, p

erio

d an

d w

ave

spee

d

Tran

sver

se a

nd lo

ngitu

dina

l wav

es

The

natu

re o

f ele

ctro

mag

netic

wav

es

The

natu

re o

f sou

nd w

aves

App

licat

ions

and

skill

s:

Expl

aini

ng th

e m

otio

n of

par

ticle

s of a

med

ium

whe

n a

wav

e pa

sses

thro

ugh

it fo

r bot

h tr

ansv

erse

and

long

itudi

nal c

ases

Sket

chin

g an

d in

terp

retin

g di

spla

cem

ent–

dist

ance

gra

phs a

nd d

ispla

cem

ent–

time

grap

hs fo

r tra

nsve

rse

and

long

itudi

nal w

aves

Solv

ing

prob

lem

s inv

olvi

ng w

ave

spee

d, fr

eque

ncy

and

wav

elen

gth

Inve

stig

atin

g th

e sp

eed

of so

und

expe

rimen

tally

Gui

danc

e:

Stud

ents

will

be

expe

cted

to d

eriv

e λ

=c

f

Stud

ents

shou

ld b

e aw

are

of th

e or

der o

f mag

nitu

de o

f the

wav

elen

gths

of

radi

o, m

icro

wav

e, in

fra-

red,

visi

ble,

ultr

avio

let,

X-ra

y an

d ga

mm

a ra

ys

Dat

a bo

okle

t ref

eren

ce:

λ=

cf

Inte

rnat

iona

l-min

dedn

ess:

Elec

trom

agne

tic w

aves

are

use

d ex

tens

ivel

y fo

r nat

iona

l and

inte

rnat

iona

l co

mm

unic

atio

n

Theo

ry o

f kno

wle

dge:

Scie

ntis

ts o

ften

tran

sfer

thei

r per

cept

ion

of ta

ngib

le a

nd v

isibl

e co

ncep

ts to

ex

plai

n sim

ilar n

on-v

isibl

e co

ncep

ts, s

uch

as in

wav

e th

eory

. How

do

scie

ntis

ts

expl

ain

conc

epts

that

hav

e no

tang

ible

or v

isibl

e qu

ality

?

Uti

lizat

ion:

Com

mun

icat

ion

usin

g bo

th so

und

(loca

lly) a

nd e

lect

rom

agne

tic w

aves

(nea

r an

d fa

r) in

volv

e w

ave

theo

ry

Emiss

ion

spec

tra

are

anal

ysed

by

com

paris

on to

the

elec

trom

agne

tic w

ave

spec

trum

(see

Che

mist

ry to

pic

2 an

d Ph

ysic

s sub

-top

ic 12

.1)

Sigh

t (se

e Bi

olog

y su

b-to

pic

A.2)

Aim

s: Aim

2: t

here

is a

com

mon

bod

y of

kno

wle

dge

and

tech

niqu

es in

volv

ed in

w

ave

theo

ry th

at is

app

licab

le a

cros

s man

y ar

eas o

f phy

sics

Aim

4: t

here

are

opp

ortu

nitie

s for

the

anal

ysis

of d

ata

to a

rriv

e at

som

e of

the

mod

els i

n th

is se

ctio

n fro

m fi

rst p

rinci

ples

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

spee

d of

wav

es in

di

ffere

nt m

edia

; det

ectio

n of

ele

ctro

mag

netic

wav

es fr

om v

ario

us so

urce

s; us

e of

ech

o m

etho

ds (o

r sim

ilar)

for d

eter

min

ing

wav

e sp

eed,

wav

elen

gth,

di

stan

ce, o

r med

ium

ela

stic

ity a

nd/o

r den

sity

Topic 4: Waves

Physics guide 49

Esse

ntia

l ide

a: A

ll w

aves

can

be

desc

ribed

by

the

sam

e se

ts o

f mat

hem

atic

al id

eas.

Det

aile

d kn

owle

dge

of o

ne a

rea

lead

s to

the

poss

ibili

ty o

f pre

dict

ion

in a

noth

er.

4.3

– W

ave

char

acte

rist

ics

Nat

ure

of sc

ienc

e:

Imag

inat

ion:

It is

spec

ulat

ed th

at p

olar

izat

ion

had

been

util

ized

by

the

Viki

ngs t

hrou

gh th

eir u

se o

f Ice

land

Spa

r ove

r 130

0 ye

ars a

go fo

r nav

igat

ion

(prio

r to

the

intr

oduc

tion

of th

e m

agne

tic c

ompa

ss).

Scie

ntis

ts a

cros

s Eur

ope

in th

e 17

th–1

9th

cent

urie

s con

tinue

d to

con

trib

ute

to w

ave

theo

ry b

y bu

ildin

g on

the

theo

ries a

nd m

odel

s pr

opos

ed a

s our

und

erst

andi

ng d

evel

oped

. (1.

4)

Und

erst

andi

ngs:

Wav

efro

nts a

nd ra

ys

Ampl

itude

and

inte

nsity

Supe

rpos

ition

Pola

rizat

ion

App

licat

ions

and

skill

s:

Sket

chin

g an

d in

terp

retin

g di

agra

ms i

nvol

ving

wav

efro

nts a

nd ra

ys

Solv

ing

prob

lem

s inv

olvi

ng a

mpl

itude

, int

ensit

y an

d th

e in

vers

e sq

uare

law

Sket

chin

g an

d in

terp

retin

g th

e su

perp

ositi

on o

f pul

ses a

nd w

aves

Des

crib

ing

met

hods

of p

olar

izat

ion

Sket

chin

g an

d in

terp

retin

g di

agra

ms i

llust

ratin

g po

lariz

ed, r

efle

cted

and

tr

ansm

itted

bea

ms

Solv

ing

prob

lem

s inv

olvi

ng M

alus

’s la

w

Gui

danc

e:

Stud

ents

will

be

expe

cted

to c

alcu

late

the

resu

ltant

of t

wo

wav

es o

r pul

ses

both

gra

phic

ally

and

alg

ebra

ical

ly

Met

hods

of p

olar

izat

ion

will

be

rest

ricte

d to

the

use

of p

olar

izin

g fil

ters

and

re

flect

ion

from

a n

on-m

etal

lic p

lane

surf

ace

Dat

a bo

okle

t ref

eren

ce:

IA2

∝ Ix

2∝

−

II

cos

02θ

=

Theo

ry o

f kno

wle

dge:

Wav

efro

nts a

nd ra

ys a

re v

isual

izat

ions

that

hel

p ou

r und

erst

andi

ng o

f re

ality

, cha

ract

eris

tic o

f mod

ellin

g in

the

phys

ical

scie

nces

. How

doe

s the

m

etho

dolo

gy u

sed

in th

e na

tura

l sci

ence

s diff

er fr

om th

e m

etho

dolo

gy u

sed

in th

e hu

man

scie

nces

?

How

muc

h de

tail

does

a m

odel

nee

d to

con

tain

to a

ccur

atel

y re

pres

ent

real

ity?

Uti

lizat

ion:

A nu

mbe

r of m

oder

n te

chno

logi

es, s

uch

as L

CD d

ispla

ys, r

ely

on p

olar

izat

ion

for t

heir

oper

atio

n

Aim

s: Aim

3: t

hese

uni

vers

al b

ehav

iour

s of w

aves

are

app

lied

in la

ter s

ectio

ns o

f the

co

urse

in m

ore

adva

nced

topi

cs, a

llow

ing

stud

ents

to g

ener

aliz

e th

e va

rious

ty

pes o

f wav

es

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

obse

rvat

ion

of

pola

rizat

ion

unde

r diff

eren

t con

ditio

ns, i

nclu

ding

the

use

of m

icro

wav

es;

supe

rpos

ition

of w

aves

; rep

rese

ntat

ion

of w

ave

type

s usin

g ph

ysic

al m

odel

s (e

g sli

nky

dem

onst

ratio

ns)

Aim

7: u

se o

f com

pute

r mod

ellin

g en

able

s stu

dent

s to

obse

rve

wav

e m

otio

n in

thre

e di

men

sions

as w

ell a

s bei

ng a

ble

to m

ore

accu

rate

ly a

djus

t wav

e ch

arac

teris

tics i

n su

perp

ositi

on d

emon

stra

tions

Topic 4: Waves

Physics guide50

Esse

ntia

l ide

a: W

aves

inte

ract

with

med

ia a

nd e

ach

othe

r in

a nu

mbe

r of w

ays t

hat c

an b

e un

expe

cted

and

use

ful.

4.4

– W

ave

beha

viou

r

Nat

ure

of sc

ienc

e:

Com

petin

g th

eorie

s: Th

e co

nflic

ting

wor

k of

Huy

gens

and

New

ton

on th

eir t

heor

ies o

f lig

ht a

nd th

e re

late

d de

bate

bet

wee

n Fr

esne

l, Ar

ago

and

Poiss

on a

re

dem

onst

ratio

ns o

f tw

o th

eorie

s tha

t wer

e va

lid y

et fl

awed

and

inco

mpl

ete.

Thi

s is a

n hi

stor

ical

exa

mpl

e of

the

prog

ress

of s

cien

ce th

at le

d to

the

acce

ptan

ce o

f the

dua

lity

of th

e na

ture

of l

ight

. (1.

9)

Und

erst

andi

ngs:

Refle

ctio

n an

d re

frac

tion

Snel

l’s la

w, c

ritic

al a

ngle

and

tota

l int

erna

l ref

lect

ion

Diff

ract

ion

thro

ugh

a sin

gle-

slit a

nd a

roun

d ob

ject

s

Inte

rfer

ence

pat

tern

s

Dou

ble-

slit i

nter

fere

nce

Path

diff

eren

ce

App

licat

ions

and

skill

s:

Sket

chin

g an

d in

terp

retin

g in

cide

nt, r

efle

cted

and

tran

smitt

ed w

aves

at

boun

darie

s bet

wee

n m

edia

Solv

ing

prob

lem

s inv

olvi

ng re

flect

ion

at a

pla

ne in

terf

ace

Solv

ing

prob

lem

s inv

olvi

ng S

nell’

s law

, crit

ical

ang

le a

nd to

tal i

nter

nal

refle

ctio

n

Det

erm

inin

g re

frac

tive

inde

x ex

perim

enta

lly

Qua

litat

ivel

y de

scrib

ing

the

diffr

actio

n pa

tter

n fo

rmed

whe

n pl

ane

wav

es a

re

inci

dent

nor

mal

ly o

n a

singl

e-sli

t

Qua

ntita

tivel

y de

scrib

ing

doub

le-s

lit in

terf

eren

ce in

tens

ity p

atte

rns

Inte

rnat

iona

l-min

dedn

ess:

Char

acte

ristic

wav

e be

havi

our h

as b

een

used

in m

any

cultu

res t

hrou

ghou

t hu

man

his

tory

, oft

en ty

ing

clos

ely

to m

yths

and

lege

nds t

hat f

orm

ed th

e ba

sis

for e

arly

scie

ntifi

c st

udie

s

Theo

ry o

f kno

wle

dge:

Huy

gens

and

New

ton

prop

osed

two

com

petin

g th

eorie

s of t

he b

ehav

iour

of

ligh

t. H

ow d

oes t

he sc

ient

ific

com

mun

ity d

ecid

e be

twee

n co

mpe

ting

theo

ries?

Uti

lizat

ion:

A sa

telli

te fo

otpr

int o

n Ea

rth

is go

vern

ed b

y th

e di

ffrac

tion

at th

e di

sh o

n th

e sa

telli

te

Appl

icat

ions

of t

he re

frac

tion

and

refle

ctio

n of

ligh

t ran

ge fr

om th

e sim

ple

plan

e m

irror

thro

ugh

the

med

ical

end

osco

pe a

nd b

eyon

d. M

any

of th

ese

appl

icat

ions

hav

e en

able

d us

to im

prov

e an

d ex

tend

our

sens

e of

visi

on

The

simpl

e id

ea o

f the

can

cella

tion

of tw

o co

here

nt li

ght r

ays r

efle

ctin

g fro

m

two

surf

aces

lead

s to

data

stor

age

in c

ompa

ct d

iscs

and

thei

r suc

cess

ors

The

phys

ical

exp

lana

tion

of th

e ra

inbo

w in

volv

es re

frac

tion

and

tota

l int

erna

l re

flect

ion.

The

brig

ht a

nd d

ark

band

s ins

ide

the

rain

bow

, sup

ernu

mer

arie

s, ca

n be

exp

lain

ed o

nly

by th

e w

ave

natu

re o

f lig

ht a

nd d

iffra

ctio

n

Topic 4: Waves

Physics guide 51

4.4

– W

ave

beha

viou

r

Gui

danc

e:

Qua

ntita

tive

desc

riptio

ns o

f ref

ract

ive

inde

x ar

e lim

ited

to li

ght r

ays p

assin

g be

twee

n tw

o or

mor

e tr

ansp

aren

t med

ia. I

f mor

e th

an tw

o m

edia

, onl

y pa

ralle

l int

erfa

ces w

ill b

e co

nsid

ered

Stud

ents

will

not

be

expe

cted

to d

eriv

e th

e do

uble

-slit

equ

atio

n

Stud

ents

shou

ld h

ave

the

oppo

rtun

ity to

obs

erve

diff

ract

ion

and

inte

rfer

ence

pa

tter

ns a

risin

g fro

m m

ore

than

one

type

of w

ave

Dat

a bo

okle

t ref

eren

ce:

n nv v

sin sin1 2

2 1

2 1

θ θ=

=

sD dλ

=

Cons

truc

tive

inte

rfer

ence

: pat

h di

ffere

nce

= nλ

Des

truc

tive

inte

rfer

ence

: pat

h di

ffere

nce

= n

1 2λ

+⎛ ⎝⎜

⎞ ⎠⎟

Aim

s: Aim

1: t

he h

isto

rical

asp

ects

of t

his t

opic

are

still

rele

vant

scie

nce

and

prov

ide

valu

able

insig

ht in

to th

e w

ork

of e

arlie

r sci

entis

ts

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

dete

rmin

atio

n of

re

frac

tive

inde

x an

d ap

plic

atio

n of

Sne

ll’s l

aw; d

eter

min

ing

cond

ition

s und

er

whi

ch to

tal i

nter

nal r

efle

ctio

n m

ay o

ccur

; exa

min

atio

n of

diff

ract

ion

patt

erns

th

roug

h ap

ertu

res a

nd a

roun

d ob

stac

les;

inve

stig

atio

n of

the

doub

le-s

lit

expe

rimen

t

Aim

8: t

he in

crea

sing

use

of d

igita

l dat

a an

d its

stor

age

dens

ity h

as

impl

icat

ions

on

indi

vidu

al p

rivac

y th

roug

h th

e pe

rman

ence

of a

dig

ital

foot

prin

t

Topic 4: Waves

Physics guide52

Esse

ntia

l ide

a: W

hen

trav

ellin

g w

aves

mee

t the

y ca

n su

perp

ose

to fo

rm st

andi

ng w

aves

in w

hich

ene

rgy

may

not

be

tran

sfer

red.

4.5

– St

andi

ng w

aves

Nat

ure

of sc

ienc

e:

Com

mon

reas

onin

g pr

oces

s: Fr

om th

e tim

e of

Pyt

hago

ras o

nwar

ds th

e co

nnec

tions

bet

wee

n th

e fo

rmat

ion

of st

andi

ng w

aves

on

strin

gs a

nd in

pip

es h

ave

been

mod

elle

d m

athe

mat

ical

ly a

nd li

nked

to th

e ob

serv

atio

ns o

f the

osc

illat

ing

syst

ems.

In th

e ca

se o

f sou

nd in

air

and

light

, the

syst

em c

an b

e vi

sual

ized

in o

rder

to re

cogn

ize

the

unde

rlyin

g pr

oces

ses o

ccur

ring

in th

e st

andi

ng w

aves

. (1.

6)

Und

erst

andi

ngs:

The

natu

re o

f sta

ndin

g w

aves

Boun

dary

con

ditio

ns

Nod

es a

nd a

ntin

odes

App

licat

ions

and

skill

s:

Des

crib

ing

the

natu

re a

nd fo

rmat

ion

of st

andi

ng w

aves

in te

rms o

f su

perp

ositi

on

Dis

tingu

ishin

g be

twee

n st

andi

ng a

nd tr

avel

ling

wav

es

Obs

ervi

ng, s

ketc

hing

and

inte

rpre

ting

stan

ding

wav

e pa

tter

ns in

strin

gs

and

pipe

s

Solv

ing

prob

lem

s inv

olvi

ng th

e fre

quen

cy o

f a h

arm

onic

, len

gth

of th

e st

andi

ng w

ave

and

the

spee

d of

the

wav

e

Gui

danc

e:

Stud

ents

will

be

expe

cted

to c

onsid

er th

e fo

rmat

ion

of st

andi

ng w

aves

from

th

e su

perp

ositi

on o

f no

mor

e th

an tw

o w

aves

Boun

dary

con

ditio

ns fo

r str

ings

are

: tw

o fix

ed b

ound

arie

s; fix

ed a

nd fr

ee

boun

dary

; tw

o fre

e bo

unda

ries

Inte

rnat

iona

l-min

dedn

ess:

The

art o

f mus

ic, w

hich

has

its s

cien

tific

bas

is in

thes

e id

eas,

is un

iver

sal t

o al

l cul

ture

s, pa

st a

nd p

rese

nt. M

any

mus

ical

inst

rum

ents

rely

hea

vily

on

the

gene

ratio

n an

d m

anip

ulat

ion

of st

andi

ng w

aves

Theo

ry o

f kno

wle

dge:

Ther

e ar

e cl

ose

links

bet

wee

n st

andi

ng w

aves

in st

rings

and

Sch

rodi

nger

’s th

eory

for t

he p

roba

bilit

y am

plitu

de o

f ele

ctro

ns in

the

atom

. App

licat

ion

to

supe

rstr

ing

theo

ry re

quire

s sta

ndin

g w

ave

patt

erns

in 11

dim

ensio

ns. W

hat i

s th

e ro

le o

f rea

son

and

imag

inat

ion

in e

nabl

ing

scie

ntis

ts to

visu

aliz

e sc

enar

ios

that

are

bey

ond

our p

hysic

al c

apab

ilitie

s?

Uti

lizat

ion:

Stud

ents

stud

ying

mus

ic sh

ould

be

enco

urag

ed to

brin

g th

eir o

wn

expe

rienc

es o

f thi

s art

form

to th

e ph

ysic

s cla

ssro

om

Topic 4: Waves

Physics guide 53

4.5

– St

andi

ng w

aves

Boun

dary

con

ditio

ns fo

r pip

es a

re: t

wo

clos

ed b

ound

arie

s; cl

osed

and

ope

n bo

unda

ry; t

wo

open

bou

ndar

ies

For s

tand

ing

wav

es in

air,

exp

lana

tions

will

not

be

requ

ired

in te

rms o

f pr

essu

re n

odes

and

pre

ssur

e an

tinod

es

The

low

est f

requ

ency

mod

e of

a st

andi

ng w

ave

is kn

own

as th

e fir

st h

arm

onic

The

term

s fun

dam

enta

l and

ove

rton

e w

ill n

ot b

e us

ed in

exa

min

atio

n qu

estio

ns

Aim

s: Aim

3: s

tude

nts a

re a

ble

to b

oth

phys

ical

ly o

bser

ve a

nd q

ualit

ativ

ely

mea

sure

th

e lo

catio

ns o

f nod

es a

nd a

ntin

odes

, fol

low

ing

the

inve

stig

ativ

e te

chni

ques

of

ear

ly sc

ient

ists

and

mus

icia

ns

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

obse

rvat

ion

of

stan

ding

wav

e pa

tter

ns in

phy

sical

obj

ects

(eg

slink

y sp

rings

); pr

edic

tion

of h

arm

onic

loca

tions

in a

n ai

r tub

e in

wat

er; d

eter

min

ing

the

frequ

ency

of

tuni

ng fo

rks;

obse

rvin

g or

mea

surin

g vi

brat

ing

viol

in/g

uita

r str

ings

Aim

8: t

he in

tern

atio

nal d

imen

sion

of th

e ap

plic

atio

n of

stan

ding

wav

es is

im

port

ant i

n m

usic

Physics guide54

Esse

ntia

l ide

a: W

hen

char

ges m

ove

an e

lect

ric c

urre

nt is

cre

ated

.

5.1

– El

ectr

ic fi

elds

Nat

ure

of sc

ienc

e:

Mod

ellin

g: E

lect

rical

theo

ry d

emon

stra

tes t

he sc

ient

ific

thou

ght i

nvol

ved

in th

e de

velo

pmen

t of a

mic

rosc

opic

mod

el (b

ehav

iour

of c

harg

e ca

rrie

rs) f

rom

mac

rosc

opic

ob

serv

atio

n. T

he h

isto

rical

dev

elop

men

t and

refin

emen

t of t

hese

scie

ntifi

c id

eas w

hen

the

mic

rosc

opic

pro

pert

ies w

ere

unkn

own

and

unob

serv

able

is te

stam

ent t

o th

e de

ep th

inki

ng sh

own

by th

e sc

ient

ists

of t

he ti

me.

(1.10

)

Und

erst

andi

ngs:

Char

ge

Elec

tric

fiel

d

Coul

omb’

s law

Elec

tric

cur

rent

Dire

ct c

urre

nt (d

c)

Pote

ntia

l diff

eren

ce

App

licat

ions

and

skill

s:

Iden

tifyi

ng tw

o fo

rms o

f cha

rge

and

the

dire

ctio

n of

the

forc

es b

etw

een

them

Solv

ing

prob

lem

s inv

olvi

ng e

lect

ric fi

elds

and

Cou

lom

b’s l

aw

Calc

ulat

ing

wor

k do

ne in

an

elec

tric

fiel

d in

bot

h jo

ules

and

ele

ctro

nvol

ts

Iden

tifyi

ng si

gn a

nd n

atur

e of

cha

rge

carr

iers

in a

met

al

Iden

tifyi

ng d

rift s

peed

of c

harg

e ca

rrie

rs

Solv

ing

prob

lem

s usin

g th

e dr

ift sp

eed

equa

tion

Solv

ing

prob

lem

s inv

olvi

ng c

urre

nt, p

oten

tial d

iffer

ence

and

cha

rge

Inte

rnat

iona

l-min

dedn

ess:

Elec

tric

ity a

nd it

s ben

efits

hav

e an

unp

aral

lele

d po

wer

to tr

ansf

orm

soci

ety

Theo

ry o

f kno

wle

dge:

Early

scie

ntis

ts id

entif

ied

posit

ive

char

ges a

s the

cha

rge

carr

iers

in

met

als;

how

ever

, the

dis

cove

ry o

f the

ele

ctro

n le

d to

the

intr

oduc

tion

of

“con

vent

iona

l” cu

rren

t dire

ctio

n. W

as th

is a

suita

ble

solu

tion

to a

maj

or sh

ift

in th

inki

ng? W

hat r

ole

do p

arad

igm

shift

s pla

y in

the

prog

ress

ion

of sc

ient

ific

know

ledg

e?

Uti

lizat

ion:

Tran

sfer

ring

ener

gy fr

om o

ne p

lace

to a

noth

er (s

ee C

hem

istry

opt

ion

C an

d

Phys

ics to

pic 1

1)

Impa

ct o

n th

e en

viro

nmen

t fro

m e

lect

ricity

gen

erat

ion

(see

Phy

sics t

opic

8

and

Chem

istry

opt

ion

sub-

topi

c C2

)

The

com

paris

on b

etw

een

the

trea

tmen

t of e

lect

ric fi

elds

and

gra

vita

tiona

l fie

lds (

see

Phys

ics t

opic

10)

Core Topi

c 5:

Ele

ctric

ity a

nd m

agne

tism

15

hou

rs

Topic 5: Electricity and magnetism

Physics guide 55

5.1

– El

ectr

ic fi

elds

Gui

danc

e:

Stud

ents

will

be

expe

cted

to a

pply

Cou

lom

b’s l

aw fo

r a ra

nge

of p

erm

ittiv

ity

valu

es

Dat

a bo

okle

t ref

eren

ce:

Iq t

=∆ ∆

Fk

qq r1

22

=

k1

40

πε=

VW q

=

EF q

=

InA

vq=

Aim

s: Aim

2: e

lect

rical

theo

ry li

es a

t the

hea

rt o

f muc

h m

oder

n sc

ienc

e an

d en

gine

erin

g

Aim

3: a

dvan

ces i

n el

ectr

ical

theo

ry h

ave

brou

ght i

mm

ense

cha

nge

to a

ll so

ciet

ies

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

dem

onst

ratio

ns

show

ing

the

effe

ct o

f an

elec

tric

fiel

d (e

g. u

sing

sem

olin

a); s

imul

atio

ns

invo

lvin

g th

e pl

acem

ent o

f one

or m

ore

poin

t cha

rges

and

det

erm

inin

g th

e re

sulta

nt fi

eld

Aim

7: u

se o

f com

pute

r sim

ulat

ions

wou

ld e

nabl

e st

uden

ts to

mea

sure

m

icro

scop

ic in

tera

ctio

ns th

at a

re ty

pica

lly v

ery

diff

icul

t in

a sc

hool

labo

rato

ry

situa

tion


Physics guide56

Esse

ntia

l ide

a: O

ne o

f the

ear

liest

use

s fo

r ele

ctric

ity w

as to

pro

duce

ligh

t and

hea

t. Th

is te

chno

logy

con

tinue

s to

hav

e a

maj

or im

pact

on

the

lives

of p

eopl

e ar

ound

th

e w

orld

.

5.2

– H

eati

ng e

ffec

t of e

lect

ric

curr

ents

Nat

ure

of sc

ienc

e:

Peer

revi

ew: A

lthou

gh O

hm a

nd B

arlo

w p

ublis

hed

thei

r fin

ding

s on

the

natu

re o

f ele

ctric

cur

rent

aro

und

the

sam

e tim

e, li

ttle

cre

denc

e w

as g

iven

to O

hm. B

arlo

w’s

inco

rrec

t la

w w

as n

ot in

itial

ly c

ritic

ized

or i

nves

tigat

ed fu

rthe

r. Th

is is

a re

flect

ion

of th

e na

ture

of a

cade

mia

of t

he ti

me,

with

phy

sics i

n G

erm

any

bein

g la

rgel

y no

n-m

athe

mat

ical

and

Ba

rlow

hel

d in

hig

h re

spec

t in

Engl

and.

It in

dica

tes t

he n

eed

for t

he p

ublic

atio

n an

d pe

er re

view

of r

esea

rch

findi

ngs i

n re

cogn

ized

scie

ntifi

c jo

urna

ls. (

4.4)

Und

erst

andi

ngs:

Circ

uit d

iagr

ams

Kirc

hhof

f’s c

ircui

t law

s

Hea

ting

effe

ct o

f cur

rent

and

its c

onse

quen

ces

Resis

tanc

e ex

pres

sed

as R

I=

V

Ohm

’s la

w

Resis

tivity

Pow

er d

issip

atio

n

App

licat

ions

and

skill

s:

Dra

win

g an

d in

terp

retin

g ci

rcui

t dia

gram

s

Iden

tifyi

ng o

hmic

and

non

-ohm

ic c

ondu

ctor

s thr

ough

a c

onsid

erat

ion

of th

e V/

I cha

ract

eris

tic g

raph

Solv

ing

prob

lem

s inv

olvi

ng p

oten

tial d

iffer

ence

, cur

rent

, cha

rge,

Kirc

hhof

f’s

circ

uit l

aws,

pow

er, r

esis

tanc

e an

d re

sistiv

ity

Inve

stig

atin

g co

mbi

natio

ns o

f res

isto

rs in

par

alle

l and

serie

s circ

uits

Des

crib

ing

idea

l and

non

-idea

l am

met

ers a

nd v

oltm

eter

s

Des

crib

ing

prac

tical

use

s of p

oten

tial d

ivid

er c

ircui

ts, i

nclu

ding

the

adva

ntag

es

of a

pot

entia

l div

ider

ove

r a se

ries r

esist

or in

con

trol

ling

a sim

ple

circ

uit

Inve

stig

atin

g on

e or

mor

e of

the

fact

ors t

hat a

ffect

resis

tanc

e ex

perim

enta

lly

Inte

rnat

iona

l-min

dedn

ess:

A se

t of u

nive

rsal

sym

bols

is ne

eded

so th

at p

hysic

ists

in d

iffer

ent c

ultu

res c

an

read

ily c

omm

unic

ate

idea

s in

scie

nce

and

engi

neer

ing

Theo

ry o

f kno

wle

dge:

Sens

e pe

rcep

tion

in e

arly

ele

ctric

al in

vest

igat

ions

was

key

to c

lass

ifyin

g th

e ef

fect

of v

ario

us p

ower

sour

ces;

how

ever

, thi

s is f

raug

ht w

ith p

ossib

le

irrev

ersib

le c

onse

quen

ces f

or th

e sc

ient

ists

invo

lved

. Can

we

still

eth

ical

ly a

nd

safe

ly u

se se

nse

perc

eptio

n in

scie

nce

rese

arch

?

Uti

lizat

ion:

Alth

ough

ther

e ar

e ne

arly

lim

itles

s way

s tha

t we

use

elec

tric

al c

ircui

ts, h

eatin

g an

d lig

htin

g ar

e tw

o of

the

mos

t wid

espr

ead

Sens

itive

dev

ices

can

em

ploy

det

ecto

rs c

apab

le o

f mea

surin

g sm

all v

aria

tions

in

pot

entia

l diff

eren

ce a

nd/o

r cur

rent

, req

uirin

g ca

refu

lly p

lann

ed c

ircui

ts a

nd

high

pre

cisio

n co

mpo

nent

s


Physics guide 57

5.2

– H

eati

ng e

ffec

t of e

lect

ric

curr

ents

Gui

danc

e:

The

filam

ent l

amp

shou

ld b

e de

scrib

ed a

s a n

on-o

hmic

dev

ice;

a m

etal

wire

at

a co

nsta

nt te

mpe

ratu

re is

an

ohm

ic d

evic

e

The

use

of n

on-id

eal v

oltm

eter

s is c

onfin

ed to

vol

tmet

ers w

ith a

con

stan

t but

fin

ite re

sista

nce

The

use

of n

on-id

eal a

mm

eter

s is c

onfin

ed to

am

met

ers w

ith a

con

stan

t but

no

n-ze

ro re

sista

nce

Appl

icat

ion

of K

irchh

off’s

circ

uit l

aws w

ill b

e lim

ited

to c

ircui

ts w

ith a

m

axim

um n

umbe

r of t

wo

sour

ce-c

arry

ing

loop

s

Dat

a bo

ok re

fere

nce:

Kirc

hoff

’s ci

rcui

t law

s:

∑V =

0 (l

oop)

∑I =

0 (j

unct

ion)

RV I

=

PVI

IRV R

==

=2

2

!R

RR

tota

l1

2=

++

!R

RR

11

1

tota

l1

2

=+

+

RA Lρ

=

Refe

r to

elec

trica

l sym

bols

on p

age

4 of

the

phys

ics d

ata

book

let

Aim

s: Aim

2: e

lect

rical

theo

ry a

nd it

s app

roac

h to

mac

ro a

nd m

icro

effe

cts

char

acte

rizes

muc

h of

the

phys

ical

app

roac

h ta

ken

in th

e an

alys

is of

the

univ

erse

Aim

3: e

lect

rical

tech

niqu

es, b

oth

prac

tical

and

theo

retic

al, p

rovi

de a

re

lativ

ely

simpl

e op

port

unity

for s

tude

nts t

o de

velo

p a

feel

ing

for t

he

argu

men

ts o

f phy

sics

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

use

of a

hot

-wire

am

met

er a

s an

hist

oric

ally

impo

rtan

t dev

ice;

com

paris

on o

f res

istiv

ity o

f a

varie

ty o

f con

duct

ors s

uch

as a

wire

at c

onst

ant t

empe

ratu

re, a

fila

men

t lam

p,

or a

gra

phite

pen

cil;

dete

rmin

atio

n of

thic

knes

s of a

pen

cil m

ark

on p

aper

; in

vest

igat

ion

of o

hmic

and

non

-ohm

ic c

ondu

ctor

cha

ract

eris

tics;

usin

g a

resis

tive

wire

wou

nd a

nd ta

ped

arou

nd th

e re

serv

oir o

f a th

erm

omet

er to

re

late

wire

resis

tanc

e to

cur

rent

in th

e w

ire a

nd te

mpe

ratu

re o

f wire

Aim

7: t

here

are

man

y so

ftw

are

and

onlin

e op

tions

for c

onst

ruct

ing

simpl

e an

d co

mpl

ex c

ircui

ts q

uick

ly to

inve

stig

ate

the

effe

ct o

f usin

g di

ffere

nt

com

pone

nts w

ithin

a c

ircui

t


Physics guide58

Esse

ntia

l ide

a: E

lect

ric c

ells

allo

w u

s to

stor

e en

ergy

in a

che

mic

al fo

rm.

5.3

– El

ectr

ic c

ells

Nat

ure

of sc

ienc

e:

Long

-ter

m ri

sks:

Scie

ntis

ts n

eed

to b

alan

ce th

e re

sear

ch in

to e

lect

ric c

ells

that

can

stor

e en

ergy

with

gre

ater

ene

rgy

dens

ity to

pro

vide

long

er d

evic

e lif

etim

es w

ith th

e lo

ng-t

erm

risk

s ass

ocia

ted

with

the

disp

osal

of t

he c

hem

ical

s inv

olve

d w

hen

batt

erie

s are

disc

arde

d. (4

.8)

Und

erst

andi

ngs:

Cells

Inte

rnal

resis

tanc

e

Seco

ndar

y ce

lls

Term

inal

pot

entia

l diff

eren

ce

Elec

trom

otiv

e fo

rce

(em

f)

App

licat

ions

and

skill

s:

Inve

stig

atin

g pr

actic

al e

lect

ric c

ells

(bot

h pr

imar

y an

d se

cond

ary)

Des

crib

ing

the

disc

harg

e ch

arac

teris

tic o

f a si

mpl

e ce

ll (v

aria

tion

of te

rmin

al

pote

ntia

l diff

eren

ce w

ith ti

me)

Iden

tifyi

ng th

e di

rect

ion

of c

urre

nt fl

ow re

quire

d to

rech

arge

a c

ell

Det

erm

inin

g in

tern

al re

sista

nce

expe

rimen

tally

Solv

ing

prob

lem

s inv

olvi

ng e

mf,

inte

rnal

resis

tanc

e an

d ot

her e

lect

rical

qu

antit

ies

Gui

danc

e:

Stud

ents

shou

ld re

cogn

ize

that

the

term

inal

pot

entia

l diff

eren

ce o

f a ty

pica

l pr

actic

al e

lect

ric c

ell l

oses

its i

nitia

l val

ue q

uick

ly, h

as a

stab

le a

nd c

onst

ant

valu

e fo

r mos

t of i

ts li

fetim

e, fo

llow

ed b

y a

rapi

d de

crea

se to

zer

o as

the

cell

disc

harg

es c

ompl

etel

y

Dat

a bo

okle

t ref

eren

ce:

IRr

()

ε=

+

Inte

rnat

iona

l-min

dedn

ess:

Batt

ery

stor

age

is im

port

ant t

o so

ciet

y fo

r use

in a

reas

such

as p

orta

ble

devi

ces,

tran

spor

tatio

n op

tions

and

bac

k-up

pow

er su

pplie

s for

med

ical

fa

cilit

ies

Theo

ry o

f kno

wle

dge:

Batt

ery

stor

age

is se

en a

s use

ful t

o so

ciet

y de

spite

the

pote

ntia

l en

viro

nmen

tal i

ssue

s sur

roun

ding

thei

r disp

osal

. Sho

uld

scie

ntis

ts b

e he

ld

mor

ally

resp

onsib

le fo

r the

long

-ter

m c

onse

quen

ces o

f the

ir in

vent

ions

and

di

scov

erie

s?

Uti

lizat

ion:

The

chem

istr

y of

ele

ctric

cel

ls (s

ee C

hem

istry

sub-

topi

cs 9

.2 a

nd C

.6)

Aim

s: Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

inve

stig

atio

n of

sim

ple

elec

trol

ytic

cel

ls us

ing

vario

us m

ater

ials

for t

he c

atho

de, a

node

and

el

ectr

olyt

e; so

ftw

are-

base

d in

vest

igat

ions

of e

lect

rical

cel

l des

ign;

com

paris

on

of th

e lif

e ex

pect

ancy

of v

ario

us b

atte

ries

Aim

8: a

lthou

gh c

ell t

echn

olog

y ca

n su

pply

ele

ctric

ity w

ithou

t dire

ct

cont

ribut

ion

from

nat

iona

l grid

syst

ems (

and

the

inhe

rent

car

bon

outp

ut

issue

s), sa

fe d

ispos

al o

f bat

terie

s and

the

chem

ical

s the

y us

e ca

n in

trod

uce

land

and

wat

er p

ollu

tion

prob

lem

s

Aim

10:

impr

ovem

ents

in c

ell t

echn

olog

y ha

s bee

n th

roug

h co

llabo

ratio

n w

ith c

hem

ists


Physics guide 59

Esse

ntia

l ide

a: T

he e

ffect

scie

ntis

ts c

all m

agne

tism

aris

es w

hen

one

char

ge m

oves

in th

e vi

cini

ty o

f ano

ther

mov

ing

char

ge.

5.4

– M

agne

tic

effe

cts o

f ele

ctri

c cu

rren

ts

Nat

ure

of sc

ienc

e:

Mod

els a

nd v

isual

izat

ion:

Mag

netic

fiel

d lin

es p

rovi

de a

pow

erfu

l visu

aliz

atio

n of

a m

agne

tic fi

eld.

His

toric

ally

, the

fiel

d lin

es h

elpe

d sc

ient

ists

and

eng

inee

rs to

und

erst

and

a lin

k th

at b

egin

s with

the

influ

ence

of o

ne m

ovin

g ch

arge

on

anot

her a

nd le

ads o

nto

rela

tivity

. (1.1

0)

Und

erst

andi

ngs:

Mag

netic

fiel

ds

Mag

netic

forc

e

App

licat

ions

and

skill

s:

Det

erm

inin

g th

e di

rect

ion

of fo

rce

on a

cha

rge

mov

ing

in a

mag

netic

fiel

d

Det

erm

inin

g th

e di

rect

ion

of fo

rce

on a

cur

rent

-car

ryin

g co

nduc

tor i

n a

mag

netic

fiel

d

Sket

chin

g an

d in

terp

retin

g m

agne

tic fi

eld

patt

erns

Det

erm

inin

g th

e di

rect

ion

of th

e m

agne

tic fi

eld

base

d on

cur

rent

dire

ctio

n

Solv

ing

prob

lem

s inv

olvi

ng m

agne

tic fo

rces

, fie

lds,

curr

ent a

nd c

harg

es

Gui

danc

e:

Mag

netic

fiel

d pa

tter

ns w

ill b

e re

stric

ted

to lo

ng st

raig

ht c

ondu

ctor

s, so

leno

ids,

and

bar m

agne

ts

Dat

a bo

okle

t ref

eren

ce:

Fqv

Bsin

θ=

FBI

Lsinθ

=

Inte

rnat

iona

l-min

dedn

ess:

The

inve

stig

atio

n of

mag

netis

m is

one

of t

he o

ldes

t stu

dies

by

man

and

was

us

ed e

xten

sivel

y by

voy

ager

s in

the

Med

iterr

anea

n an

d be

yond

thou

sand

s of

year

s ago

Theo

ry o

f kno

wle

dge:

Fiel

d pa

tter

ns p

rovi

de a

visu

aliz

atio

n of

a c

ompl

ex p

heno

men

on, e

ssen

tial t

o an

und

erst

andi

ng o

f thi

s top

ic. W

hy m

ight

it b

e us

eful

to re

gard

kno

wle

dge

in a

sim

ilar w

ay, u

sing

the

met

apho

r of k

now

ledg

e as

a m

ap –

a si

mpl

ified

re

pres

enta

tion

of re

ality

?

Uti

lizat

ion:

Onl

y co

mpa

rativ

ely

rece

ntly

has

the

mag

netic

com

pass

bee

n su

pers

eded

by

diffe

rent

tech

nolo

gies

aft

er h

undr

eds o

f yea

rs o

f our

dep

ende

nce

on it

Mod

ern

med

ical

scan

ners

rely

hea

vily

on

the

stro

ng, u

nifo

rm m

agne

tic fi

elds

pr

oduc

ed b

y de

vice

s tha

t util

ize

supe

rcon

duct

ors

Part

icle

acc

eler

ator

s suc

h as

the

Larg

e H

adro

n Co

llide

r at C

ERN

rely

on

a va

riety

of

pre

cise

mag

nets

for a

ligni

ng th

e pa

rtic

le b

eam

s

Aim

s: Aim

s 2 a

nd 9

: visu

aliz

atio

ns fr

eque

ntly

pro

vide

us w

ith in

sight

s int

o th

e ac

tion

of m

agne

tic fi

elds

; how

ever

, the

visu

aliz

atio

ns th

emse

lves

hav

e th

eir

own

limita

tions

Aim

7: c

ompu

ter-b

ased

sim

ulat

ions

ena

ble

the

visu

aliz

atio

n of

el

ectr

omag

netic

fiel

ds in

thre

e-di

men

siona

l spa

ce

Physics guide60

Esse

ntia

l ide

a: A

forc

e ap

plie

d pe

rpen

dicu

lar t

o its

disp

lace

men

t can

resu

lt in

circ

ular

mot

ion.

6.1

– Ci

rcul

ar m

otio

n

Nat

ure

of sc

ienc

e:

Obs

erva

ble

univ

erse

: Obs

erva

tions

and

subs

eque

nt d

educ

tions

led

to th

e re

aliz

atio

n th

at th

e fo

rce

mus

t act

radi

ally

inw

ards

in a

ll ca

ses o

f circ

ular

mot

ion.

(1.1)

Und

erst

andi

ngs:

Perio

d, fr

eque

ncy,

ang

ular

disp

lace

men

t and

ang

ular

vel

ocity

Cent

ripet

al fo

rce

Cent

ripet

al a

ccel

erat

ion

App

licat

ions

and

skill

s:

Iden

tifyi

ng th

e fo

rces

pro

vidi

ng th

e ce

ntrip

etal

forc

es su

ch a

s ten

sion,

fric

tion,

gr

avita

tiona

l, el

ectr

ical

, or m

agne

tic

Solv

ing

prob

lem

s inv

olvi

ng c

entr

ipet

al fo

rce,

cen

trip

etal

acc

eler

atio

n, p

erio

d,

frequ

ency

, ang

ular

disp

lace

men

t, lin

ear s

peed

and

ang

ular

vel

ocity

Qua

litat

ivel

y an

d qu

antit

ativ

ely

desc

ribin

g ex

ampl

es o

f circ

ular

mot

ion

incl

udin

g ca

ses o

f ver

tical

and

hor

izon

tal c

ircul

ar m

otio

n

Gui

danc

e:

Bank

ing

will

be

cons

ider

ed q

ualit

ativ

ely

only

Dat

a bo

okle

t ref

eren

ce:

rν

ω=

av r

rT4

22 2π

==

Fm

v rm

r2

2ω

==

Inte

rnat

iona

l-min

dedn

ess:

Inte

rnat

iona

l col

labo

ratio

n is

need

ed in

est

ablis

hing

effe

ctiv

e ro

cket

laun

ch

sites

to b

enef

it sp

ace

prog

ram

s

Theo

ry o

f kno

wle

dge:

Fouc

ault’

s pen

dulu

m g

ives

a si

mpl

e ob

serv

able

pro

of o

f the

rota

tion

of th

e ea

rth,

whi

ch is

larg

ely

unob

serv

able

. How

can

we

have

kno

wle

dge

of th

ings

th

at a

re u

nobs

erva

ble?

Uti

lizat

ion:

Mot

ion

of c

harg

ed p

artic

les i

n m

agne

tic fi

elds

(see

Phy

sics s

ub-t

opic

5.4

)

Mas

s spe

ctro

met

ry (s

ee C

hem

istry

sub-

topi

cs 2

.1 a

nd 11

.3)

Play

grou

nd a

nd a

mus

emen

t par

k rid

es o

ften

use

the

prin

cipl

es o

f circ

ular

m

otio

n in

thei

r des

ign

Aim

s: Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

mas

s on

a st

ring;

ob

serv

atio

n an

d qu

antif

icat

ion

of lo

op-t

he-lo

op e

xper

ienc

es; f

rictio

n of

a

mas

s on

a tu

rnta

ble

Aim

7: t

echn

olog

y ha

s allo

wed

for m

ore

accu

rate

and

pre

cise

mea

sure

men

ts

of c

ircul

ar m

otio

n, in

clud

ing

data

logg

ers f

or fo

rce

mea

sure

men

ts a

nd v

ideo

an

alys

is of

obj

ects

mov

ing

in c

ircul

ar m

otio

n

Topi

c 6:

Circ

ular

mot

ion

and

grav

itatio

n 5

hour

s

Core

Topic 6: Circular motion and gravitation

Physics guide 61

Esse

ntia

l ide

a: T

he N

ewto

nian

idea

of g

ravi

tatio

nal f

orce

act

ing

betw

een

two

sphe

rical

bod

ies

and

the

law

s of

mec

hani

cs c

reat

e a

mod

el th

at c

an b

e us

ed to

cal

cula

te th

e m

otio

n of

pla

nets

.

6.2

– N

ewto

n’s l

aw o

f gra

vita

tion

Nat

ure

of sc

ienc

e:

Law

s: N

ewto

n’s l

aw o

f gra

vita

tion

and

the

law

s of m

echa

nics

are

the

foun

datio

n fo

r det

erm

inist

ic cl

assic

al p

hysic

s. Th

ese

can

be u

sed

to m

ake

pred

ictio

ns b

ut d

o no

t exp

lain

why

th

e ob

serv

ed p

heno

men

a ex

ist. (2

.4)

Und

erst

andi

ngs:

New

ton’

s law

of g

ravi

tatio

n

Gra

vita

tiona

l fie

ld st

reng

th

App

licat

ions

and

skill

s:

Des

crib

ing

the

rela

tions

hip

betw

een

grav

itatio

nal f

orce

and

cen

trip

etal

forc

e

Appl

ying

New

ton’

s law

of g

ravi

tatio

n to

the

mot

ion

of a

n ob

ject

in c

ircul

ar

orbi

t aro

und

a po

int m

ass

Solv

ing

prob

lem

s inv

olvi

ng g

ravi

tatio

nal f

orce

, gra

vita

tiona

l fie

ld st

reng

th,

orbi

tal s

peed

and

orb

ital p

erio

d

Det

erm

inin

g th

e re

sulta

nt g

ravi

tatio

nal f

ield

stre

ngth

due

to tw

o bo

dies

Gui

danc

e:

New

ton’

s law

of g

ravi

tatio

n sh

ould

be

exte

nded

to sp

heric

al m

asse

s of

unifo

rm d

ensit

y by

ass

umin

g th

at th

eir m

ass i

s con

cent

rate

d at

thei

r cen

tre

Gra

vita

tiona

l fie

ld st

reng

th a

t a p

oint

is th

e fo

rce

per u

nit m

ass e

xper

ienc

ed b

y a

smal

l poi

nt m

ass a

t tha

t poi

nt

Calc

ulat

ions

of t

he re

sulta

nt g

ravi

tatio

nal f

ield

stre

ngth

due

to tw

o bo

dies

will

be

rest

ricte

d to

poi

nts a

long

the

stra

ight

line

join

ing

the

bodi

es

Dat

a bo

okle

t ref

eren

ce:

FG

Mm r2

=

gF m

=

gG

M r2=

Theo

ry o

f kno

wle

dge:

The

law

s of m

echa

nics

alo

ng w

ith th

e la

w o

f gra

vita

tion

crea

te th

e de

term

inis

tic n

atur

e of

cla

ssic

al p

hysic

s. Ar

e cl

assic

al p

hysic

s and

mod

ern

phys

ics c

ompa

tible

? Do

othe

r are

as o

f kno

wle

dge

also

hav

e a

simila

r div

ision

be

twee

n cl

assic

al a

nd m

oder

n in

thei

r his

toric

al d

evel

opm

ent?

Uti

lizat

ion:

The

law

of g

ravi

tatio

n is

esse

ntia

l in

desc

ribin

g th

e m

otio

n of

sate

llite

s, pl

anet

s, m

oons

and

ent

ire g

alax

ies

Com

paris

on to

Cou

lom

b’s l

aw (s

ee P

hysic

s sub

-top

ic 5

.1)

Aim

s: Aim

4: t

he th

eory

of g

ravi

tatio

n w

hen

com

bine

d an

d sy

nthe

sized

with

the

rest

of t

he la

ws o

f mec

hani

cs a

llow

s det

aile

d pr

edic

tions

abo

ut th

e fu

ture

po

sitio

n an

d m

otio

n of

pla

nets

Physics guide62

Esse

ntia

l ide

a: In

the

mic

rosc

opic

wor

ld e

nerg

y is

disc

rete

.

7.1

– D

iscr

ete

ener

gy a

nd ra

dioa

ctiv

ity

Nat

ure

of sc

ienc

e:

Acci

dent

al d

iscov

ery:

Rad

ioac

tivity

was

disc

over

ed b

y ac

cide

nt w

hen

Becq

uere

l dev

elop

ed p

hoto

grap

hic

film

that

had

acc

iden

tally

bee

n ex

pose

d to

radi

atio

n fro

m

radi

oact

ive

rock

s. Th

e m

arks

on

the

phot

ogra

phic

film

seen

by

Becq

uere

l pro

babl

y w

ould

not

lead

to a

nyth

ing

furt

her f

or m

ost p

eopl

e. W

hat B

ecqu

erel

did

was

to

corr

elat

e th

e pr

esen

ce o

f the

mar

ks w

ith th

e pr

esen

ce o

f the

radi

oact

ive

rock

s and

inve

stig

ate

the

situa

tion

furt

her.

(1.4

)

Und

erst

andi

ngs:

Disc

rete

ene

rgy

and

disc

rete

ene

rgy

leve

ls

Tran

sitio

ns b

etw

een

ener

gy le

vels

Radi

oact

ive

deca

y

Fund

amen

tal f

orce

s and

thei

r pro

pert

ies

Alph

a pa

rtic

les,

beta

par

ticle

s and

gam

ma

rays

Hal

f-life

Abso

rptio

n ch

arac

teris

tics o

f dec

ay p

artic

les

Isot

opes

Back

grou

nd ra

diat

ion

Inte

rnat

iona

l-min

dedn

ess:

The

geop

oliti

cs o

f the

pas

t 60+

yea

rs h

ave

been

gre

atly

influ

ence

d by

the

exis

tenc

e of

nuc

lear

wea

pons

Theo

ry o

f kno

wle

dge:

The

role

of l

uck/

sere

ndip

ity in

succ

essf

ul sc

ient

ific

disc

over

y is

alm

ost

inev

itabl

y ac

com

pani

ed b

y a

scie

ntifi

cally

cur

ious

min

d th

at w

ill p

ursu

e th

e ou

tcom

e of

the

“luck

y” e

vent

. To

wha

t ext

ent m

ight

scie

ntifi

c di

scov

erie

s tha

t ha

ve b

een

desc

ribed

as b

eing

the

resu

lt of

luck

act

ually

be

bett

er d

escr

ibed

as

bein

g th

e re

sult

of re

ason

or i

ntui

tion?

Topi

c 7:

Ato

mic

, nuc

lear

and

par

ticle

phy

sics

14 h

ours

Core

Topic 7: Atomic, nuclear and particle physics

Physics guide 63

7.1

– D

iscr

ete

ener

gy a

nd ra

dioa

ctiv

ity

App

licat

ions

and

skill

s:

Des

crib

ing

the

emiss

ion

and

abso

rptio

n sp

ectr

um o

f com

mon

gas

es

Solv

ing

prob

lem

s inv

olvi

ng a

tom

ic sp

ectr

a, in

clud

ing

calc

ulat

ing

the

wav

elen

gth

of p

hoto

ns e

mitt

ed d

urin

g at

omic

tran

sitio

ns

Com

plet

ing

deca

y eq

uatio

ns fo

r alp

ha a

nd b

eta

deca

y

Det

erm

inin

g th

e ha

lf-lif

e of

a n

uclid

e fro

m a

dec

ay c

urve

Inve

stig

atin

g ha

lf-lif

e ex

perim

enta

lly (o

r by

simul

atio

n)

Gui

danc

e:

Stud

ents

will

be

requ

ired

to so

lve

prob

lem

s on

radi

oact

ive

deca

y in

volv

ing

only

inte

gral

num

bers

of h

alf-l

ives

Stud

ents

will

be

expe

cted

to in

clud

e th

e ne

utrin

o an

d an

tineu

trin

o in

bet

a de

cay

equa

tions

Dat

a bo

okle

t ref

eren

ce:

Ehf

=

hc Eλ

=

Uti

lizat

ion:

Know

ledg

e of

radi

oact

ivity

, rad

ioac

tive

subs

tanc

es a

nd th

e ra

dioa

ctiv

e de

cay

law

are

cru

cial

in m

oder

n nu

clea

r med

icin

e

How

to d

eal w

ith th

e ra

dioa

ctiv

e ou

tput

of n

ucle

ar d

ecay

is im

port

ant i

n th

e de

bate

ove

r nuc

lear

pow

er st

atio

ns (s

ee P

hysic

s sub

-top

ic 8

.1)

Carb

on d

atin

g is

used

in p

rovi

ding

evi

denc

e fo

r evo

lutio

n (s

ee B

iolo

gy su

b-to

pic

5.1)

Expo

nent

ial f

unct

ions

(see

Mat

hem

atic

al st

udie

s SL

sub-

topi

c 6.

4; M

athe

mat

ics

HL

sub-

topi

c 2.

4)

Aim

s: Aim

8: t

he u

se o

f rad

ioac

tive

mat

eria

ls po

ses e

nviro

nmen

tal d

ange

rs th

at

mus

t be

addr

esse

d at

all

stag

es o

f res

earc

h

Aim

9: t

he u

se o

f rad

ioac

tive

mat

eria

ls re

quire

s the

dev

elop

men

t of s

afe

expe

rimen

tal p

ract

ices

and

met

hods

for h

andl

ing

radi

oact

ive

mat

eria

ls


Physics guide64

Esse

ntia

l ide

a: E

nerg

y ca

n be

rele

ased

in n

ucle

ar d

ecay

s and

reac

tions

as a

resu

lt of

the

rela

tions

hip

betw

een

mas

s and

ene

rgy.

7.2

– N

ucle

ar re

acti

ons

Nat

ure

of sc

ienc

e:

Patt

erns

, tre

nds a

nd d

iscre

panc

ies:

Gra

phs o

f bin

ding

ene

rgy

per n

ucle

on a

nd o

f neu

tron

num

ber v

ersu

s pro

ton

num

ber r

evea

l unm

ista

kabl

e pa

tter

ns. T

his a

llow

s sc

ient

ists

to m

ake

pred

ictio

ns o

f iso

tope

cha

ract

eris

tics b

ased

on

thes

e gr

aphs

. (3.

1)

Und

erst

andi

ngs:

The

unifi

ed a

tom

ic m

ass u

nit

Mas

s def

ect a

nd n

ucle

ar b

indi

ng e

nerg

y

Nuc

lear

fiss

ion

and

nucl

ear f

usio

n

App

licat

ions

and

skill

s:

Solv

ing

prob

lem

s inv

olvi

ng m

ass d

efec

t and

bin

ding

ene

rgy

Solv

ing

prob

lem

s inv

olvi

ng th

e en

ergy

rele

ased

in ra

dioa

ctiv

e de

cay,

nuc

lear

fis

sion

and

nucl

ear f

usio

n

Sket

chin

g an

d in

terp

retin

g th

e ge

nera

l sha

pe o

f the

cur

ve o

f ave

rage

bin

ding

en

ergy

per

nuc

leon

aga

inst

nuc

leon

num

ber

Theo

ry o

f kno

wle

dge:

The

acce

ptan

ce th

at m

ass a

nd e

nerg

y ar

e eq

uiva

lent

was

a m

ajor

par

adig

m

shift

in p

hysic

s. H

ow h

ave

othe

r par

adig

m sh

ifts c

hang

ed th

e di

rect

ion

of

scie

nce?

Hav

e th

ere

been

sim

ilar p

arad

igm

shift

s in

othe

r are

as o

f kno

wle

dge?

Uti

lizat

ion:

Our

und

erst

andi

ng o

f the

ene

rget

ics o

f the

nuc

leus

has

led

to w

ays t

o pr

oduc

e el

ectr

icity

from

nuc

lei b

ut a

lso

to th

e de

velo

pmen

t of v

ery

dest

ruct

ive

wea

pons

The

chem

istr

y of

nuc

lear

reac

tions

(see

Che

mist

ry o

ptio

n su

b-to

pics

C.3

an

d C.

7)


Physics guide 65

7.2

– N

ucle

ar re

acti

ons

Gui

danc

e:

Stud

ents

mus

t be

able

to c

alcu

late

cha

nges

in te

rms o

f mas

s or b

indi

ng

ener

gy

Bind

ing

ener

gy m

ay b

e de

fined

in te

rms o

f ene

rgy

requ

ired

to c

ompl

etel

y se

para

te th

e nu

cleo

ns o

r the

ene

rgy

rele

ased

whe

n a

nucl

eus i

s for

med

from

its

nuc

leon

s

Dat

a bo

okle

t ref

eren

ce:

Em

c2∆

=∆

Aim

s: Aim

5: s

ome

of th

e iss

ues r

aise

d by

the

use

of n

ucle

ar p

ower

tran

scen

d na

tiona

l bou

ndar

ies a

nd re

quire

the

colla

bora

tion

of sc

ient

ists

from

man

y di

ffere

nt n

atio

ns

Aim

8: t

he d

evel

opm

ent o

f nuc

lear

pow

er a

nd n

ucle

ar w

eapo

ns ra

ises

ver

y se

rious

mor

al a

nd e

thic

al q

uest

ions

: who

shou

ld b

e al

low

ed to

pos

sess

nu

clea

r pow

er a

nd n

ucle

ar w

eapo

ns a

nd w

ho sh

ould

mak

e th

ese

deci

sions

? Th

ere

also

serio

us e

nviro

nmen

tal i

ssue

s ass

ocia

ted

with

the

nucl

ear w

aste

of

nucl

ear p

ower

pla

nts.


Physics guide66

Esse

ntia

l ide

a: It

is b

elie

ved

that

all

the

mat

ter a

roun

d us

is m

ade

up o

f fun

dam

enta

l par

ticle

s cal

led

quar

ks a

nd le

pton

s. It

is kn

own

that

mat

ter h

as a

hie

rarc

hica

l str

uctu

re

with

qua

rks

mak

ing

up n

ucle

ons,

nuc

leon

s m

akin

g up

nuc

lei,

nucl

ei a

nd e

lect

rons

mak

ing

up a

tom

s an

d at

oms

mak

ing

up m

olec

ules

. In

this

hie

rarc

hica

l str

uctu

re, t

he

smal

lest

scal

e is

seen

for q

uark

s and

lept

ons (

10–1

8 m).

7.3

– Th

e st

ruct

ure

of m

atte

r

Nat

ure

of sc

ienc

e:

Pred

ictio

ns: O

ur p

rese

nt u

nder

stan

ding

of m

atte

r is c

alle

d th

e St

anda

rd M

odel

, con

sistin

g of

six

quar

ks a

nd si

x le

pton

s. Q

uark

s wer

e po

stul

ated

on

a co

mpl

etel

y m

athe

mat

ical

bas

is in

ord

er to

exp

lain

pat

tern

s in

prop

ertie

s of p

artic

les.

(1.9

)

Colla

bora

tion:

It w

as m

uch

late

r tha

t lar

ge-s

cale

col

labo

rativ

e ex

perim

enta

tion

led

to th

e di

scov

ery

of th

e pr

edic

ted

fund

amen

tal p

artic

les.

(4.3

)

Und

erst

andi

ngs:

Qua

rks,

lept

ons a

nd th

eir a

ntip

artic

les

Had

rons

, bar

yons

and

mes

ons

The

cons

erva

tion

law

s of c

harg

e, b

aryo

n nu

mbe

r, le

pton

num

ber a

nd

stra

ngen

ess

The

natu

re a

nd ra

nge

of th

e st

rong

nuc

lear

forc

e, w

eak

nucl

ear f

orce

and

el

ectr

omag

netic

forc

e

Exch

ange

par

ticle

s

Feyn

man

dia

gram

s

Conf

inem

ent

The

Hig

gs b

oson

App

licat

ions

and

skill

s:

Des

crib

ing

the

Ruth

erfo

rd-G

eige

r-Mar

sden

exp

erim

ent t

hat l

ed to

the

disc

over

y of

the

nucl

eus

Appl

ying

con

serv

atio

n la

ws i

n pa

rtic

le re

actio

ns

Des

crib

ing

prot

ons a

nd n

eutr

ons i

n te

rms o

f qua

rks

Com

parin

g th

e in

tera

ctio

n st

reng

ths o

f the

fund

amen

tal f

orce

s, in

clud

ing

grav

ity

Des

crib

ing

the

med

iatio

n of

the

fund

amen

tal f

orce

s thr

ough

exc

hang

e pa

rtic

les

Inte

rnat

iona

l-min

dedn

ess:

Rese

arch

into

par

ticle

phy

sics r

equi

res e

ver-i

ncre

asin

g fu

ndin

g, le

adin

g to

de

bate

s in

gove

rnm

ents

and

inte

rnat

iona

l res

earc

h or

gani

zatio

ns o

n th

e fa

ir al

loca

tion

of p

reci

ous f

inan

cial

reso

urce

s

Theo

ry o

f kno

wle

dge:

Doe

s the

bel

ief i

n th

e ex

iste

nce

of fu

ndam

enta

l par

ticle

s mea

n th

at it

is

just

ifiab

le to

see

phys

ics a

s bei

ng m

ore

impo

rtan

t tha

n ot

her a

reas

of

know

ledg

e?

Uti

lizat

ion:

An u

nder

stan

ding

of p

artic

le p

hysic

s is n

eede

d to

det

erm

ine

the

final

fate

of

the

univ

erse

(see

Phy

sics o

ptio

n su

b-to

pics

D.3

and

D.4

)

Aim

s: Aim

1: t

he re

sear

ch th

at d

eals

with

the

fund

amen

tal s

truc

ture

of m

atte

r is

inte

rnat

iona

l in

natu

re a

nd is

a c

halle

ngin

g an

d st

imul

atin

g ad

vent

ure

for

thos

e w

ho ta

ke p

art

Aim

4: p

artic

le p

hysic

s inv

olve

s the

ana

lysis

and

eva

luat

ion

of v

ery

larg

e am

ount

s of d

ata

Aim

6: s

tude

nts c

ould

inve

stig

ate

the

scat

terin

g an

gle

of a

lpha

par

ticle

s as

a fu

nctio

n of

the

aim

ing

erro

r, or

the

min

imum

dis

tanc

e of

app

roac

h as

a

func

tion

of th

e in

itial

kin

etic

ene

rgy

of th

e al

pha

part

icle


Physics guide 67

7.3

– Th

e st

ruct

ure

of m

atte

r

Sket

chin

g an

d in

terp

retin

g sim

ple

Feyn

man

dia

gram

s

Des

crib

ing

why

free

qua

rks a

re n

ot o

bser

ved

Gui

danc

e:

A qu

alita

tive

desc

riptio

n of

the

stan

dard

mod

el is

requ

ired

Dat

a bo

okle

t ref

eren

ce:

Char

geQ

uark

sBa

ryon

nu

mbe

r

e2 3

uc

t1 3

e1 3−

ds

b1 3

All q

uark

s hav

e a

stra

ngen

ess n

umbe

r of

0 ex

cept

the

stra

nge

quar

k th

at h

as a

stra

ngen

ess

num

ber o

f –1

Char

geLe

pton

s

–1e

μτ

0υ e

υ μυ τ

All l

epto

ns h

ave

a le

pton

nu

mbe

r of 1

and

ant

ilept

ons

have

a le

pton

num

ber o

f –1

Aim

8: s

cien

tific

and

gov

ernm

ent o

rgan

izat

ions

are

ask

ed if

the

fund

ing

for

part

icle

phy

sics r

esea

rch

coul

d be

spen

t on

othe

r res

earc

h or

soci

al n

eeds

Gra

vita

tion

alW

eak

Elec

trom

agne

tic

Stro

ng

Part

icle

s exp

erie

ncin

gAl

lQ

uark

s, le

pton

sCh

arge

dQ

uark

s, gl

uons

Par

ticl

es m

edia

ting

Gra

vito

nW

+ , W– , Z

0γ

Glu

ons

Physics guide68

Esse

ntia

l ide

a: T

he c

onst

ant n

eed

for n

ew e

nerg

y so

urce

s im

plie

s de

cisi

ons

that

may

hav

e a

serio

us e

ffec

t on

the

envi

ronm

ent.

The

finite

qua

ntity

of f

ossi

l fue

ls a

nd th

eir

impl

icat

ion

in g

loba

l war

min

g ha

s led

to th

e de

velo

pmen

t of a

ltern

ativ

e so

urce

s of e

nerg

y. T

his c

ontin

ues t

o be

an

area

of r

apid

ly c

hang

ing

tech

nolo

gica

l inn

ovat

ion.

8.1

– En

ergy

sour

ces

Nat

ure

of sc

ienc

e:

Risk

s and

pro

blem

-sol

ving

: Sin

ce e

arly

tim

es m

anki

nd u

nder

stoo

d th

e vi

tal r

ole

of h

arne

ssin

g en

ergy

and

larg

e-sc

ale

prod

uctio

n of

ele

ctric

ity h

as im

pact

ed a

ll le

vels

of

soci

ety.

Pro

cess

es w

here

ene

rgy

is tr

ansf

orm

ed re

quire

hol

istic

app

roac

hes t

hat i

nvol

ve m

any

area

s of k

now

ledg

e. R

esea

rch

and

deve

lopm

ent o

f alte

rnat

ive

ener

gy so

urce

s ha

s lac

ked

supp

ort i

n so

me

coun

trie

s for

eco

nom

ic a

nd p

oliti

cal r

easo

ns. S

cien

tists

, how

ever

, hav

e co

ntin

ued

to c

olla

bora

te a

nd sh

are

new

tech

nolo

gies

that

can

redu

ce

our d

epen

denc

e on

non

-ren

ewab

le e

nerg

y so

urce

s. (4

.8)

Und

erst

andi

ngs:

Spec

ific

ener

gy a

nd e

nerg

y de

nsity

of f

uel s

ourc

es

Sank

ey d

iagr

ams

Prim

ary

ener

gy so

urce

s

Elec

tric

ity a

s a se

cond

ary

and

vers

atile

form

of e

nerg

y

Rene

wab

le a

nd n

on-r

enew

able

ene

rgy

sour

ces

App

licat

ions

and

skill

s:

Solv

ing

spec

ific

ener

gy a

nd e

nerg

y de

nsity

pro

blem

s

Sket

chin

g an

d in

terp

retin

g Sa

nkey

dia

gram

s

Des

crib

ing

the

basic

feat

ures

of f

ossil

fuel

pow

er st

atio

ns, n

ucle

ar p

ower

st

atio

ns, w

ind

gene

rato

rs, p

umpe

d st

orag

e hy

droe

lect

ric sy

stem

s and

sola

r po

wer

cel

ls

Solv

ing

prob

lem

s rel

evan

t to

ener

gy tr

ansf

orm

atio

ns in

the

cont

ext o

f the

se

gene

ratin

g sy

stem

s

Inte

rnat

iona

l-min

dedn

ess:

The

prod

uctio

n of

ene

rgy

from

foss

il fu

els h

as a

cle

ar im

pact

on

the

wor

ld w

e liv

e in

and

ther

efor

e in

volv

es g

loba

l thi

nkin

g. T

he g

eogr

aphi

c co

ncen

trat

ions

of

foss

il fu

els h

ave

led

to p

oliti

cal c

onfli

ct a

nd e

cono

mic

ineq

ualit

ies.

The

prod

uctio

n of

ene

rgy

thro

ugh

alte

rnat

ive

ener

gy re

sour

ces d

eman

ds n

ew

leve

ls of

inte

rnat

iona

l col

labo

ratio

n.

Theo

ry o

f kno

wle

dge:

The

use

of n

ucle

ar e

nerg

y in

spire

s a ra

nge

of e

mot

iona

l res

pons

es fr

om

scie

ntis

ts a

nd so

ciet

y. H

ow c

an a

ccur

ate

scie

ntifi

c ris

k as

sess

men

t be

unde

rtak

en in

em

otio

nally

cha

rged

are

as?

Uti

lizat

ion:

Gen

erat

ors f

or e

lect

rical

pro

duct

ion

and

engi

nes f

or m

otio

n ha

ve

revo

lutio

nize

d th

e w

orld

(see

Phy

sics s

ub-t

opic

s 5.4

and

11.2

)

The

engi

neer

ing

behi

nd a

ltern

ativ

e en

ergy

sour

ces i

s inf

luen

ced

by d

iffer

ent

area

s of p

hysic

s (se

e Ph

ysic

s sub

-top

ics 3

.2, 5

.4 a

nd B

.2)

Topi

c 8:

Ene

rgy

prod

uctio

n 8

hour

s

Core

Topic 8: Energy production

Physics guide 69

8.1

– En

ergy

sour

ces

Disc

ussin

g sa

fety

issu

es a

nd ri

sks a

ssoc

iate

d w

ith th

e pr

oduc

tion

of

nucl

ear p

ower

Des

crib

ing

the

diffe

renc

es b

etw

een

phot

ovol

taic

cel

ls an

d so

lar

heat

ing

pane

ls

Gui

danc

e:

Spec

ific

ener

gy h

as u

nits

of J

kg–1

; ene

rgy

dens

ity h

as u

nits

of J

m–3

The

desc

riptio

n of

the

basic

feat

ures

of n

ucle

ar p

ower

stat

ions

mus

t inc

lude

th

e us

e of

con

trol

rods

, mod

erat

ors a

nd h

eat e

xcha

nger

s

Der

ivat

ion

of th

e w

ind

gene

rato

r equ

atio

n is

not r

equi

red

but a

n aw

aren

ess o

f re

leva

nt a

ssum

ptio

ns a

nd li

mita

tions

is re

quire

d

Stud

ents

are

exp

ecte

d to

be

awar

e of

new

and

dev

elop

ing

tech

nolo

gies

w

hich

may

bec

ome

impo

rtan

t dur

ing

the

life

of th

is gu

ide

Dat

a bo

okle

t ref

eren

ce:

Pow

eren

ergy

time

=

ρν=

APo

wer

1 23

Ener

gy d

ensit

y (s

ee C

hem

istry

sub-

topi

c C.

1)

Carb

on re

cycl

ing

(see

Bio

logy

sub-

topi

c 4.

3)

Aim

s: Aim

4: t

he p

rodu

ctio

n of

pow

er in

volv

es m

any

diffe

rent

scie

ntifi

c di

scip

lines

an

d re

quire

s the

eva

luat

ion

and

synt

hesis

of s

cien

tific

info

rmat

ion

Aim

8: t

he p

rodu

ctio

n of

ene

rgy

has w

ide

econ

omic

, env

ironm

enta

l, m

oral

an

d et

hica

l dim

ensio

ns


Physics guide70

Esse

ntia

l ide

a: F

or si

mpl

ified

mod

ellin

g pu

rpos

es th

e Ea

rth

can

be tr

eate

d as

a b

lack

-bod

y ra

diat

or a

nd th

e at

mos

pher

e tr

eate

d as

a g

rey-

body

.

8.2

– Th

erm

al e

nerg

y tr

ansf

er

Nat

ure

of sc

ienc

e:

Sim

ple

and

com

plex

mod

ellin

g: T

he k

inet

ic th

eory

of g

ases

is a

sim

ple

mat

hem

atic

al m

odel

that

pro

duce

s a g

ood

appr

oxim

atio

n of

the

beha

viou

r of r

eal g

ases

. Sci

entis

ts

are

also

att

empt

ing

to m

odel

the

Eart

h’s c

limat

e, w

hich

is a

far m

ore

com

plex

syst

em. A

dvan

ces i

n da

ta a

vaila

bilit

y an

d th

e ab

ility

to in

clud

e m

ore

proc

esse

s in

the

mod

els

toge

ther

with

con

tinue

d te

stin

g an

d sc

ient

ific

deba

te o

n th

e va

rious

mod

els w

ill im

prov

e th

e ab

ility

to p

redi

ct c

limat

e ch

ange

mor

e ac

cura

tely

. (1.1

2)

Und

erst

andi

ngs:

Cond

uctio

n, c

onve

ctio

n an

d th

erm

al ra

diat

ion

Blac

k-bo

dy ra

diat

ion

Albe

do a

nd e

miss

ivity

The

sola

r con

stan

t

The

gree

nhou

se e

ffect

Ener

gy b

alan

ce in

the

Eart

h su

rfac

e–at

mos

pher

e sy

stem

App

licat

ions

and

skill

s:

Sket

chin

g an

d in

terp

retin

g gr

aphs

show

ing

the

varia

tion

of in

tens

ity w

ith

wav

elen

gth

for b

odie

s em

ittin

g th

erm

al ra

diat

ion

at d

iffer

ent t

empe

ratu

res

Solv

ing

prob

lem

s inv

olvi

ng th

e St

efan

–Bol

tzm

ann

law

and

Wie

n’s

disp

lace

men

t law

Des

crib

ing

the

effe

cts o

f the

Ear

th’s

atm

osph

ere

on th

e m

ean

surf

ace

tem

pera

ture

Solv

ing

prob

lem

s inv

olvi

ng a

lbed

o, e

miss

ivity

, sol

ar c

onst

ant a

nd th

e Ea

rth’

s av

erag

e te

mpe

ratu

re

Inte

rnat

iona

l-min

dedn

ess:

The

conc

ern

over

the

poss

ible

impa

ct o

f clim

ate

chan

ge h

as re

sulte

d in

an

abun

danc

e of

inte

rnat

iona

l pre

ss c

over

age,

man

y po

litic

al d

iscus

sions

with

in

and

betw

een

natio

ns, a

nd th

e co

nsid

erat

ion

of p

eopl

e, c

orpo

ratio

ns, a

nd

the

envi

ronm

ent w

hen

deci

ding

on

futu

re p

lans

for o

ur p

lane

t. IB

gra

duat

es

shou

ld b

e aw

are

of th

e sc

ienc

e be

hind

man

y of

thes

e sc

enar

ios.

Theo

ry o

f kno

wle

dge:

The

deba

te a

bout

glo

bal w

arm

ing

illus

trat

es th

e di

ffic

ultie

s tha

t aris

e w

hen

scie

ntis

ts c

anno

t alw

ays a

gree

on

the

inte

rpre

tatio

n of

the

data

, esp

ecia

lly

as th

e so

lutio

n w

ould

invo

lve

larg

e-sc

ale

actio

n th

roug

h in

tern

atio

nal

gove

rnm

ent c

oope

ratio

n. W

hen

scie

ntis

ts d

isag

ree,

how

do

we

deci

de

betw

een

com

petin

g th

eorie

s?


Physics guide 71

8.2

– Th

erm

al e

nerg

y tr

ansf

er

Gui

danc

e:

Disc

ussio

n of

con

duct

ion

and

conv

ectio

n w

ill b

e qu

alita

tive

only

Disc

ussio

n of

con

duct

ion

is lim

ited

to in

term

olec

ular

and

ele

ctro

n co

llisio

ns

Disc

ussio

n of

con

vect

ion

is lim

ited

to si

mpl

e ga

s or l

iqui

d tr

ansf

er v

ia d

ensit

y di

ffere

nces

The

abso

rptio

n of

infr

ared

radi

atio

n by

gre

enho

use

gase

s sho

uld

be d

escr

ibed

in

term

s of t

he m

olec

ular

ene

rgy

leve

ls an

d th

e su

bseq

uent

em

issio

n of

ra

diat

ion

in a

ll di

rect

ions

The

gree

nhou

se g

ases

to b

e co

nsid

ered

are

CH

4, H

2O, C

O2 a

nd N

2O. I

t is

suff

icie

nt fo

r stu

dent

s to

know

that

eac

h ha

s bot

h na

tura

l and

man

-mad

e or

igin

s.

Eart

h’s a

lbed

o va

ries d

aily

and

is d

epen

dent

on

seas

on (c

loud

form

atio

ns)

and

latit

ude.

The

glo

bal a

nnua

l mea

n al

bedo

will

be

take

n to

be

0.3

(30%

) fo

r Ear

th.

Dat

a bo

okle

t ref

eren

ce:

Pe

AT4

σ=

T(m

etre

s)2.

9010

kelv

inm

ax

3

λ(

)=

×−

IA

pow

er= albe

doto

tals

catte

red

pow

erto

tali

ncid

entp

ower

=

Uti

lizat

ion:

Clim

ate

mod

els a

nd th

e va

riatio

n in

det

ail/p

roce

sses

incl

uded

Envi

ronm

enta

l che

mis

try

(see

Che

mist

ry o

ptio

n to

pic

C)

Clim

ate

chan

ge (s

ee B

iolo

gy su

b-to

pic

4.4

and

Envi

ronm

enta

l sys

tem

s and

so

ciet

ies t

opic

s 5 a

nd 6

)

The

norm

al d

istr

ibut

ion

curv

e is

expl

ored

in M

athe

mat

ical

stud

ies S

L

sub-

topi

c 4.

1

Aim

s: A

im 4

: thi

s top

ic g

ives

stud

ents

the

oppo

rtun

ity to

und

erst

and

the

wid

e ra

nge

of sc

ient

ific

anal

ysis

behi

nd c

limat

e ch

ange

issu

es

Aim

6: s

imul

atio

ns o

f ene

rgy

exch

ange

in th

e Ea

rth

surf

ace–

atm

osph

ere

syst

em

Aim

8: w

hile

scie

nce

has t

he a

bilit

y to

ana

lyse

and

pos

sibly

hel

p so

lve

clim

ate

chan

ge is

sues

, stu

dent

s sho

uld

be a

war

e of

the

impa

ct o

f sci

ence

on

the

initi

atio

n of

con

ditio

ns th

at a

llow

ed c

limat

e ch

ange

due

to h

uman

co

ntrib

utio

ns to

occ

ur. S

tude

nts s

houl

d al

so b

e aw

are

of th

e w

ay sc

ienc

e ca

n be

use

d to

pro

mot

e th

e in

tere

sts o

f one

side

of t

he d

ebat

e on

clim

ate

chan

ge

(or,

conv

erse

ly, t

o hi

nder

deb

ate)

.

Physics guide72

Esse

ntia

l ide

a: T

he so

lutio

n of

the

harm

onic

osc

illat

or c

an b

e fr

amed

aro

und

the

varia

tion

of k

inet

ic a

nd p

oten

tial e

nerg

y in

the

syst

em.

9.1

– Si

mpl

e ha

rmon

ic m

otio

n

Nat

ure

of sc

ienc

e:

Insig

hts:

The

equa

tion

for s

impl

e ha

rmon

ic m

otio

n (S

HM

) can

be

solv

ed a

naly

tical

ly a

nd n

umer

ical

ly. P

hysic

ists

use

such

solu

tions

to h

elp

them

to v

isual

ize

the

beha

viou

r of

the

osci

llato

r. Th

e us

e of

the

equa

tions

is v

ery

pow

erfu

l as a

ny o

scill

atio

n ca

n be

des

crib

ed in

term

s of a

com

bina

tion

of h

arm

onic

osc

illat

ors.

Num

eric

al m

odel

ling

of

osci

llato

rs is

impo

rtan

t in

the

desig

n of

ele

ctric

al c

ircui

ts. (

1.11)

Und

erst

andi

ngs:

The

defin

ing

equa

tion

of S

HM

Ener

gy c

hang

es

App

licat

ions

and

skill

s:

Solv

ing

prob

lem

s inv

olvi

ng a

ccel

erat

ion,

vel

ocity

and

disp

lace

men

t dur

ing

simpl

e ha

rmon

ic m

otio

n, b

oth

grap

hica

lly a

nd a

lgeb

raic

ally

Des

crib

ing

the

inte

rcha

nge

of k

inet

ic a

nd p

oten

tial e

nerg

y du

ring

simpl

e ha

rmon

ic m

otio

n

Solv

ing

prob

lem

s inv

olvi

ng e

nerg

y tr

ansf

er d

urin

g sim

ple

harm

onic

mot

ion,

bo

th g

raph

ical

ly a

nd a

lgeb

raic

ally

Gui

danc

e

Cont

exts

for t

his s

ub-t

opic

incl

ude

the

simpl

e pe

ndul

um a

nd a

mas

s-sp

ring

syst

em

Uti

lizat

ion:

Four

ier a

naly

sis a

llow

s us t

o de

scrib

e al

l per

iodi

c os

cilla

tions

in te

rms o

f sim

ple

harm

onic

osc

illat

ors.

The

mat

hem

atic

s of s

impl

e ha

rmon

ic m

otio

n is

cruc

ial t

o an

y ar

eas o

f sci

ence

and

tech

nolo

gy w

here

osc

illat

ions

occ

ur

The

inte

rcha

nge

of e

nerg

ies i

n os

cilla

tion

is im

port

ant i

n el

ectr

ical

ph

enom

ena

Qua

drat

ic fu

nctio

ns (s

ee M

athe

mat

ics H

L su

b-to

pic

2.6;

Mat

hem

atic

s SL

sub-

topi

c 2.

4; M

athe

mat

ical

stud

ies S

L su

b-to

pic

6.3)

Trig

onom

etric

func

tions

(see

Mat

hem

atic

s SL

sub-

topi

c 3.

4)

Topi

c 9:

Wav

e ph

enom

ena

17 h

ours

Addi

tiona

l hig

her l

evel

Topic 9: Wave phenomena

Physics guide 73

9.1

– Si

mpl

e ha

rmon

ic m

otio

n

Dat

a bo

okle

t ref

eren

ce:

T2ω

π=

ax

2ω

=−

xx

tx

xt

sin;

cos

00

ωω

==

vx

tv

xt

cos

;sin

00

ωω

ωω

==

−

vx

x02

2ω

()

=±

−

Em

xx

1 2K

20

22

ω(

)=

−

Em

x1 2

T2

02ω

=

Tl g

Pend

ulum

:2π

= Tm k

Mas

ssp

ring:

2π−

=

Aim

s: Aim

4: s

tude

nts c

an u

se th

is to

pic

to d

evel

op th

eir a

bilit

y to

synt

hesiz

e co

mpl

ex a

nd d

iver

se sc

ient

ific

info

rmat

ion

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

inve

stig

atio

n of

sim

ple

or to

rsio

nal p

endu

lum

s; m

easu

ring

the

vibr

atio

ns o

f a tu

ning

fork

; fu

rthe

r ext

ensio

ns o

f the

exp

erim

ents

con

duct

ed in

sub-

topi

c 4.

1. B

y us

ing

the

forc

e la

w, a

stud

ent c

an, w

ith it

erat

ion,

det

erm

ine

the

beha

viou

r of a

n ob

ject

un

der s

impl

e ha

rmon

ic m

otio

n. T

he it

erat

ive

appr

oach

(num

eric

al so

lutio

n),

with

giv

en in

itial

con

ditio

ns, a

pplie

s bas

ic u

nifo

rm a

ccel

erat

ion

equa

tions

in

succ

essiv

e sm

all t

ime

incr

emen

ts. A

t eac

h in

crem

ent,

final

val

ues b

ecom

e th

e fo

llow

ing

initi

al c

ondi

tions

.

Aim

7: t

he o

bser

vatio

n of

sim

ple

harm

onic

mot

ion

and

the

varia

bles

affe

cted

ca

n be

eas

ily fo

llow

ed in

com

pute

r sim

ulat

ions


Physics guide74

Esse

ntia

l ide

a: S

ingl

e-sli

t diff

ract

ion

occu

rs w

hen

a w

ave

is in

cide

nt u

pon

a sli

t of a

ppro

xim

atel

y th

e sa

me

size

as th

e w

avel

engt

h.

9.2

– Si

ngle

-slit

dif

frac

tion

Nat

ure

of sc

ienc

e:

Dev

elop

men

t of t

heor

ies:

Whe

n lig

ht p

asse

s thr

ough

an

aper

ture

the

sum

mat

ion

of a

ll pa

rts o

f the

wav

e le

ads t

o an

inte

nsity

pat

tern

that

is fa

r rem

oved

from

the

geom

etric

al sh

adow

that

sim

ple

theo

ry p

redi

cts.

(1.9

)

Und

erst

andi

ngs:

The

natu

re o

f sin

gle-

slit d

iffra

ctio

n

App

licat

ions

and

skill

s:

Des

crib

ing

the

effe

ct o

f slit

wid

th o

n th

e di

ffrac

tion

patt

ern

Det

erm

inin

g th

e po

sitio

n of

firs

t int

erfe

renc

e m

inim

um

Qua

litat

ivel

y de

scrib

ing

singl

e-sli

t diff

ract

ion

patt

erns

pro

duce

d fro

m w

hite

lig

ht a

nd fr

om a

rang

e of

mon

ochr

omat

ic li

ght f

requ

enci

es

Gui

danc

e:

Onl

y re

ctan

gula

r slit

s nee

d to

be

cons

ider

ed

Diff

ract

ion

arou

nd a

n ob

ject

(rat

her t

han

thro

ugh

a sli

t) do

es n

ot n

eed

to b

e co

nsid

ered

in th

is su

b-to

pic

(see

Phy

sics s

ub-t

opic

4.4

)

Theo

ry o

f kno

wle

dge:

Are

expl

anat

ions

in sc

ienc

e di

ffere

nt fr

om e

xpla

natio

ns in

oth

er a

reas

of

know

ledg

e su

ch a

s his

tory

?

Uti

lizat

ion:

X-ra

y di

ffrac

tion

is an

impo

rtan

t too

l of t

he c

ryst

allo

grap

her a

nd th

e m

ater

ial

scie

ntis

t

Aim

s: Aim

2: t

his t

opic

pro

vide

s a b

ody

of k

now

ledg

e th

at c

hara

cter

izes

the

way

th

at sc

ienc

e is

subj

ect t

o m

odifi

catio

n w

ith ti

me

Aim

6: e

xper

imen

ts c

an b

e co

mbi

ned

with

thos

e fro

m su

b-to

pics

4.4

and

9.3


Physics guide 75

9.2

– Si

ngle

-slit

dif

frac

tion

Stud

ents

will

be

expe

cted

to b

e aw

are

of th

e ap

prox

imat

e ra

tios o

f suc

cess

ive

inte

nsity

max

ima

for s

ingl

e-sli

t int

erfe

renc

e pa

tter

ns

Calc

ulat

ions

will

be

limite

d to

a d

eter

min

atio

n of

the

posit

ion

of th

e fir

st

min

imum

for s

ingl

e-sli

t int

erfe

renc

e pa

tter

ns u

sing

the

appr

oxim

atio

n eq

uatio

n

Dat

a bo

okle

t ref

eren

ce:

bθ

λ=


Physics guide76

Esse

ntia

l ide

a: In

terf

eren

ce p

atte

rns f

rom

mul

tiple

slits

and

thin

film

s pro

duce

acc

urat

ely

repe

atab

le p

atte

rns.

9.3

– In

terf

eren

ce

Nat

ure

of sc

ienc

e:

Curio

sity:

Obs

erve

d pa

tter

ns o

f irid

esce

nce

in a

nim

als,

such

as t

he sh

imm

er o

f pea

cock

feat

hers

, led

scie

ntis

ts to

dev

elop

the

theo

ry o

f thi

n fil

m in

terf

eren

ce. (

1.5)

Sere

ndip

ity: T

he fi

rst l

abor

ator

y pr

oduc

tion

of th

in fi

lms w

as a

ccid

enta

l. (1

.5)

Und

erst

andi

ngs:

Youn

g’s d

oubl

e-sli

t exp

erim

ent

Mod

ulat

ion

of tw

o-sli

t int

erfe

renc

e pa

tter

n by

one

-slit

diff

ract

ion

effe

ct

Mul

tiple

slit

and

diffr

actio

n gr

atin

g in

terf

eren

ce p

atte

rns

Thin

film

inte

rfer

ence

App

licat

ions

and

skill

s:

Qua

litat

ivel

y de

scrib

ing

two-

slit i

nter

fere

nce

patt

erns

, inc

ludi

ng m

odul

atio

n by

one

-slit

diff

ract

ion

effe

ct

Inve

stig

atin

g Yo

ung’

s dou

ble-

slit e

xper

imen

tally

Sket

chin

g an

d in

terp

retin

g in

tens

ity g

raph

s of d

oubl

e-sli

t int

erfe

renc

e pa

tter

ns

Solv

ing

prob

lem

s inv

olvi

ng th

e di

ffrac

tion

grat

ing

equa

tion

Des

crib

ing

cond

ition

s nec

essa

ry fo

r con

stru

ctiv

e an

d de

stru

ctiv

e in

terf

eren

ce

from

thin

film

s, in

clud

ing

phas

e ch

ange

at i

nter

face

and

effe

ct o

f ref

ract

ive

inde

x

Solv

ing

prob

lem

s inv

olvi

ng in

terf

eren

ce fr

om th

in fi

lms

Theo

ry o

f kno

wle

dge:

Mos

t tw

o-sli

t int

erfe

renc

e de

scrip

tions

can

be

mad

e w

ithou

t ref

eren

ce to

the

one-

slit m

odul

atio

n ef

fect

. To

wha

t lev

el c

an sc

ient

ists

igno

re p

arts

of a

mod

el

for s

impl

icity

and

cla

rity?

Uti

lizat

ion:

Com

pact

dis

cs a

re a

com

mer

cial

exa

mpl

e of

the

use

of d

iffra

ctio

n gr

atin

gs

Thin

film

s are

use

d to

pro

duce

ant

i-ref

lect

ion

coat

ings

Aim

s: Aim

4: t

wo

scie

ntifi

c co

ncep

ts (d

iffra

ctio

n an

d in

terf

eren

ce) c

ome

toge

ther

in

this

sub-

topi

c, a

llow

ing

stud

ents

to a

naly

se a

nd sy

nthe

size

a w

ider

rang

e of

sc

ient

ific

info

rmat

ion

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

obse

rvin

g th

e us

e of

diff

ract

ion

grat

ings

in sp

ectr

osco

pes;

anal

ysis

of th

in so

ap fi

lms;

soun

d w

ave

and

mic

row

ave

inte

rfer

ence

pat

tern

ana

lysis

Aim

9: t

he ra

y ap

proa

ch to

the

desc

riptio

n of

thin

film

inte

rfer

ence

is o

nly

an a

ppro

xim

atio

n. S

tude

nts s

houl

d re

cogn

ize

the

limita

tions

of s

uch

a vi

sual

izat

ion


Physics guide 77

9.3

– In

terf

eren

ce

Gui

danc

e:

Stud

ents

shou

ld b

e in

trod

uced

to in

terf

eren

ce p

atte

rns f

rom

a v

arie

ty o

f co

here

nt so

urce

s suc

h as

(but

not

lim

ited

to) e

lect

rom

agne

tic w

aves

, sou

nd

and

simul

ated

dem

onst

ratio

ns

Diff

ract

ion

grat

ing

patt

erns

are

rest

ricte

d to

thos

e fo

rmed

at n

orm

al in

cide

nce

The

trea

tmen

t of t

hin

film

inte

rfer

ence

is c

onfin

ed to

par

alle

l-sid

ed fi

lms a

t no

rmal

inci

denc

e

The

cons

truc

tive

inte

rfer

ence

and

des

truc

tive

inte

rfer

ence

form

ulae

list

ed

belo

w a

nd in

the

data

boo

klet

app

ly to

spec

ific

case

s of p

hase

cha

nges

at

inte

rfac

es a

nd a

re n

ot g

ener

ally

true

Dat

a bo

okle

t ref

eren

ce:

nd

sinλ

θ=

Cons

truc

tive

inte

rfer

ence

: dn

m2

1 2λ

=+

⎛ ⎝⎜⎞ ⎠⎟

Des

truc

tive

inte

rfer

ence

: dn

m2

λ=


Physics guide78

Esse

ntia

l ide

a: R

esol

utio

n pl

aces

an

abso

lute

lim

it on

the

exte

nt to

whi

ch a

n op

tical

or o

ther

syst

em c

an se

para

te im

ages

of o

bjec

ts.

9.4

– Re

solu

tion

Nat

ure

of sc

ienc

e:

Impr

oved

tech

nolo

gy: T

he R

ayle

igh

crite

rion

is th

e lim

it of

reso

lutio

n. C

ontin

uing

adv

ance

men

t in

tech

nolo

gy su

ch a

s lar

ge d

iam

eter

dish

es o

r len

ses o

r the

use

of s

mal

ler

wav

elen

gth

lase

rs p

ushe

s the

lim

its o

f wha

t we

can

reso

lve.

(1.8

)

Und

erst

andi

ngs:

The

size

of a

diff

ract

ing

aper

ture

The

reso

lutio

n of

sim

ple

mon

ochr

omat

ic tw

o-so

urce

syst

ems

App

licat

ions

and

skill

s:

Solv

ing

prob

lem

s inv

olvi

ng th

e Ra

ylei

gh c

riter

ion

for l

ight

em

itted

by

two

sour

ces d

iffra

cted

at a

sing

le sl

it

Reso

lvan

ce o

f diff

ract

ion

grat

ings

Gui

danc

e:

Proo

f of t

he d

iffra

ctio

n gr

atin

g re

solv

ance

equ

atio

n is

not r

equi

red

Dat

a bo

okle

t ref

eren

ce:

b1.

22θ

λ=

Rm

Nλ λ

=∆

=

Inte

rnat

iona

l-min

dedn

ess:

Sate

llite

use

for c

omm

erci

al a

nd p

oliti

cal p

urpo

ses i

s dic

tate

d by

the

reso

lutio

n ca

pabi

litie

s of t

he sa

telli

te

Theo

ry o

f kno

wle

dge:

The

reso

lutio

n lim

its se

t by

Daw

es a

nd R

ayle

igh

are

capa

ble

of b

eing

su

rpas

sed

by th

e co

nstr

uctio

n of

hig

h qu

ality

tele

scop

es. A

re w

e ca

pabl

e of

br

eaki

ng o

ther

lim

its o

f sci

entif

ic k

now

ledg

e w

ith o

ur a

dvan

cing

tech

nolo

gy?

Uti

lizat

ion:

An o

ptic

al o

r oth

er re

cept

ion

syst

em m

ust b

e ab

le to

reso

lve

the

inte

nded

im

ages

. Thi

s has

impl

icat

ions

for s

atel

lite

tran

smiss

ions

, rad

io a

stro

nom

y an

d m

any

othe

r app

licat

ions

in p

hysic

s and

tech

nolo

gy (s

ee P

hysic

s opt

ion

C)

Stor

age

med

ia su

ch a

s com

pact

disc

s (an

d th

eir v

aria

nts)

and

CCD

sens

ors r

ely

on re

solu

tion

limits

to st

ore

and

repr

oduc

e m

edia

acc

urat

ely

Aim

s: Aim

3: t

his s

ub-t

opic

hel

ps b

ridge

the

gap

betw

een

wav

e th

eory

and

real

-life

ap

plic

atio

ns

Aim

8: t

he n

eed

for c

omm

unic

atio

n be

twee

n na

tiona

l com

mun

ities

via

sa

telli

tes r

aise

s the

aw

aren

ess o

f the

soci

al a

nd e

cono

mic

impl

icat

ions

of

tech

nolo

gy


Physics guide 79

Esse

ntia

l ide

a: T

he D

oppl

er e

ffect

des

crib

es th

e ph

enom

enon

of w

avel

engt

h/fre

quen

cy sh

ift w

hen

rela

tive

mot

ion

occu

rs.

9.5

– D

oppl

er e

ffec

t

Nat

ure

of sc

ienc

e:

Tech

nolo

gy: A

lthou

gh o

rigin

ally

bas

ed o

n ph

ysic

al o

bser

vatio

ns o

f the

pitc

h of

fast

mov

ing

sour

ces o

f sou

nd, t

he D

oppl

er e

ffect

has

an

impo

rtan

t rol

e in

man

y di

ffere

nt

area

s suc

h as

evi

denc

e fo

r the

exp

ansio

n of

the

univ

erse

and

gen

erat

ing

imag

es u

sed

in w

eath

er re

port

s and

in m

edic

ine.

(5.5

)

Und

erst

andi

ngs:

The

Dop

pler

effe

ct fo

r sou

nd w

aves

and

ligh

t wav

es

App

licat

ions

and

skill

s:

Sket

chin

g an

d in

terp

retin

g th

e D

oppl

er e

ffect

whe

n th

ere

is re

lativ

e m

otio

n be

twee

n so

urce

and

obs

erve

r

Des

crib

ing

situa

tions

whe

re th

e D

oppl

er e

ffect

can

be

utili

zed

Solv

ing

prob

lem

s inv

olvi

ng th

e ch

ange

in fr

eque

ncy

or w

avel

engt

h ob

serv

ed

due

to th

e D

oppl

er e

ffect

to d

eter

min

e th

e ve

loci

ty o

f the

sour

ce/o

bser

ver

Gui

danc

e:

For e

lect

rom

agne

tic w

aves

, the

app

roxi

mat

e eq

uatio

n sh

ould

be

used

for a

ll ca

lcul

atio

ns

Situ

atio

ns to

be

disc

usse

d sh

ould

incl

ude

the

use

of D

oppl

er e

ffect

in ra

dars

an

d in

med

ical

phy

sics,

and

its si

gnifi

canc

e fo

r the

red-

shift

in th

e lig

ht sp

ectr

a of

rece

ding

gal

axie

s

Dat

a bo

okle

t ref

eren

ce:

Mov

ing

sour

ce: f

fv

vu s

′=±

⎛ ⎝⎜⎞ ⎠⎟

Mov

ing

obse

rver

: ff

vu v

0′=

±⎛ ⎝⎜

⎞ ⎠⎟

f fv c

λ λ∆

=∆

≈

Inte

rnat

iona

l-min

dedn

ess:

Rada

r usa

ge is

affe

cted

by

the

Dop

pler

effe

ct a

nd m

ust b

e co

nsid

ered

for

appl

icat

ions

usin

g th

is te

chno

logy

Theo

ry o

f kno

wle

dge:

How

impo

rtan

t is s

ense

per

cept

ion

in e

xpla

inin

g sc

ient

ific

idea

s suc

h as

the

Dop

pler

effe

ct?

Uti

lizat

ion:

Astr

onom

y re

lies o

n th

e an

alys

is of

the

Dop

pler

effe

ct w

hen

deal

ing

with

fast

m

ovin

g ob

ject

s (se

e Ph

ysic

s opt

ion

D)

Aim

s: Aim

2: t

he D

oppl

er e

ffect

nee

ds to

be

cons

ider

ed in

var

ious

app

licat

ions

of

tech

nolo

gy th

at u

tiliz

e w

ave

theo

ry

Aim

6: s

pect

ral d

ata

and

imag

es o

f rec

edin

g ga

laxi

es a

re a

vaila

ble

from

pr

ofes

siona

l ast

rono

mic

al o

bser

vato

ries f

or a

naly

sis

Aim

7: c

ompu

ter s

imul

atio

ns o

f the

Dop

pler

effe

ct a

llow

stud

ents

to v

isual

ize

com

plex

and

mos

tly u

nobs

erva

ble

situa

tions

Physics guide80

Esse

ntia

l ide

a: E

lect

ric c

harg

es a

nd m

asse

s eac

h in

fluen

ce th

e sp

ace

arou

nd th

em a

nd th

at in

fluen

ce c

an b

e re

pres

ente

d th

roug

h th

e co

ncep

t of f

ield

s.

10.1

– D

escr

ibin

g fie

lds

Nat

ure

of sc

ienc

e:

Para

digm

shift

: The

mov

e fro

m d

irect

, obs

erva

ble

actio

ns b

eing

resp

onsib

le fo

r inf

luen

ce o

n an

obj

ect t

o ac

cept

ance

of a

fiel

d’s “

actio

n at

a d

ista

nce”

requ

ired

a pa

radi

gm

shift

in th

e w

orld

of s

cien

ce. (

2.3)

Und

erst

andi

ngs:

Gra

vita

tiona

l fie

lds

Elec

tros

tatic

fiel

ds

Elec

tric

pot

entia

l and

gra

vita

tiona

l pot

entia

l

Fiel

d lin

es

Equi

pote

ntia

l sur

face

s

App

licat

ions

and

skill

s:

Repr

esen

ting

sour

ces o

f mas

s and

cha

rge,

line

s of e

lect

ric a

nd g

ravi

tatio

nal

forc

e, a

nd fi

eld

patt

erns

usin

g an

app

ropr

iate

sym

bolis

m

Map

ping

fiel

ds u

sing

pote

ntia

l

Des

crib

ing

the

conn

ectio

n be

twee

n eq

uipo

tent

ial s

urfa

ces a

nd fi

eld

lines

Theo

ry o

f kno

wle

dge:

Alth

ough

gra

vita

tiona

l and

ele

ctro

stat

ic fo

rces

dec

reas

e w

ith th

e sq

uare

of

dist

ance

and

will

onl

y be

com

e ze

ro a

t inf

inite

sepa

ratio

n, fr

om a

pra

ctic

al

stan

dpoi

nt th

ey b

ecom

e ne

glig

ible

at m

uch

smal

ler d

ista

nces

. How

do

scie

ntis

ts d

ecid

e w

hen

an e

ffect

is so

smal

l tha

t it c

an b

e ig

nore

d?

Uti

lizat

ion:

Know

ledg

e of

vec

tor a

naly

sis is

use

ful f

or th

is su

b-to

pic

(see

Phy

sics

sub-

topi

c 1.

3)

Aim

s: Aim

9: m

odel

s dev

elop

ed fo

r ele

ctric

and

gra

vita

tiona

l fie

lds u

sing

lines

of

forc

es a

llow

pre

dict

ions

to b

e m

ade

but h

ave

limita

tions

in te

rms o

f the

fini

te

wid

th o

f a li

ne

Topi

c 10

: Fie

lds

11 h

ours

Addi

tiona

l hig

her l

evel

Topic 10: Fields

Physics guide 81

10.1

– D

escr

ibin

g fie

lds

Gui

danc

e:

Elec

tros

tatic

fiel

ds a

re re

stric

ted

to th

e ra

dial

fiel

ds a

roun

d po

int o

r sph

eric

al

char

ges,

the

field

bet

wee

n tw

o po

int c

harg

es a

nd th

e un

iform

fiel

ds b

etw

een

char

ged

para

llel p

late

s

Gra

vita

tiona

l fie

lds a

re re

stric

ted

to th

e ra

dial

fiel

ds a

roun

d po

int o

r sph

eric

al

mas

ses a

nd th

e (a

ssum

ed) u

nifo

rm fi

eld

clos

e to

the

surf

ace

of m

assiv

e ce

lest

ial b

odie

s and

pla

neta

ry b

odie

s

Stud

ents

shou

ld re

cogn

ize

that

no

wor

k is

done

in m

ovin

g ch

arge

or m

ass o

n an

equ

ipot

entia

l sur

face

Dat

a bo

okle

t ref

eren

ce:

Wq

V e=

∆

Wm

V g=

∆

Topic 10: Fields

Physics guide82

Esse

ntia

l ide

a: S

imila

r app

roac

hes c

an b

e ta

ken

in a

naly

sing

elec

tric

al a

nd g

ravi

tatio

nal p

oten

tial p

robl

ems.

10.2

– F

ield

s at w

ork

Nat

ure

of sc

ienc

e:

Com

mun

icat

ion

of sc

ient

ific

expl

anat

ions

: The

abi

lity

to a

pply

fiel

d th

eory

to th

e un

obse

rvab

le (c

harg

es) a

nd th

e m

assiv

ely

scal

ed (m

otio

n of

sate

llite

s) re

quire

d sc

ient

ists

to

dev

elop

new

way

s to

inve

stig

ate,

ana

lyse

and

repo

rt fi

ndin

gs to

a g

ener

al p

ublic

use

d to

scie

ntifi

c di

scov

erie

s bas

ed o

n ta

ngib

le a

nd d

isce

rnib

le e

vide

nce.

(5.1)

Und

erst

andi

ngs:

Pote

ntia

l and

pot

entia

l ene

rgy

Pote

ntia

l gra

dien

t

Pote

ntia

l diff

eren

ce

Esca

pe sp

eed

Orb

ital m

otio

n, o

rbita

l spe

ed a

nd o

rbita

l ene

rgy

Forc

es a

nd in

vers

e-sq

uare

law

beh

avio

ur

App

licat

ions

and

skill

s:

Det

erm

inin

g th

e po

tent

ial e

nerg

y of

a p

oint

mas

s and

the

pote

ntia

l ene

rgy

of

a po

int c

harg

e

Solv

ing

prob

lem

s inv

olvi

ng p

oten

tial e

nerg

y

Det

erm

inin

g th

e po

tent

ial i

nsid

e a

char

ged

sphe

re

Solv

ing

prob

lem

s inv

olvi

ng th

e sp

eed

requ

ired

for a

n ob

ject

to g

o in

to o

rbit

arou

nd a

pla

net a

nd fo

r an

obje

ct to

esc

ape

the

grav

itatio

nal f

ield

of a

pla

net

Solv

ing

prob

lem

s inv

olvi

ng o

rbita

l ene

rgy

of c

harg

ed p

artic

les i

n ci

rcul

ar

orbi

tal m

otio

n an

d m

asse

s in

circ

ular

orb

ital m

otio

n

Solv

ing

prob

lem

s inv

olvi

ng fo

rces

on

char

ges a

nd m

asse

s in

radi

al a

nd

unifo

rm fi

elds

Uti

lizat

ion:

The

glob

al p

ositi

onin

g sy

stem

dep

ends

on

com

plet

e un

ders

tand

ing

of

sate

llite

mot

ion

Geo

stat

iona

ry/p

olar

sate

llite

s

The

acce

lera

tion

of c

harg

ed p

artic

les i

n pa

rtic

le a

ccel

erat

ors a

nd in

man

y m

edic

al im

agin

g de

vice

s dep

ends

on

the

pres

ence

of e

lect

ric fi

elds

(see

Ph

ysic

s opt

ion

sub-

topi

c C.

4)

Aim

s: Aim

2: N

ewto

n’s l

aw o

f gra

vita

tion

and

Coul

omb’

s law

form

par

t of t

he

stru

ctur

e kn

own

as “c

lass

ical

phy

sics”

. Thi

s bod

y of

kno

wle

dge

has p

rovi

ded

the

met

hods

and

tool

s of a

naly

sis u

p to

the

adve

nt o

f the

theo

ry o

f rel

ativ

ity

and

the

quan

tum

theo

ry

Aim

4: t

he th

eorie

s of g

ravi

tatio

n an

d el

ectr

osta

tic in

tera

ctio

ns a

llow

s for

a

grea

t syn

thes

is in

the

desc

riptio

n of

a la

rge

num

ber o

f phe

nom

ena

Topic 10: Fields

Physics guide 83

10.2

– F

ield

s at w

ork

Gui

danc

e:

Orb

ital m

otio

n of

a sa

telli

te a

roun

d a

plan

et is

rest

ricte

d to

a c

onsid

erat

ion

of

circ

ular

orb

its (l

inks

to 6

.1 a

nd 6

.2)

Both

uni

form

and

radi

al fi

elds

nee

d to

be

cons

ider

ed

Stud

ents

shou

ld re

cogn

ize

that

line

s of f

orce

can

be

two-

dim

ensio

nal

repr

esen

tatio

ns o

f thr

ee-d

imen

siona

l fie

lds

Stud

ents

shou

ld a

ssum

e th

at th

e el

ectr

ic fi

eld

ever

ywhe

re b

etw

een

para

llel

plat

es is

uni

form

with

edg

e ef

fect

s occ

urrin

g be

yond

the

limits

of t

he p

late

s.

Dat

a bo

okle

t ref

eren

ce:

VGM r

g=

−V

kq re

=

gV rg

=−

∆ ∆E

V re=

−∆ ∆

Em

VGM

m rP

g=

=−

EqV

kqq r

Pe

12

==

FG

mm r

G1

22

=F

kq

q rE

12

2=

VGM r

2es

c=

VGM r

orbi

t=

Physics guide84

Esse

ntia

l ide

a: T

he m

ajor

ity o

f ele

ctric

ity g

ener

ated

thro

ugho

ut th

e w

orld

is g

ener

ated

by

mac

hine

s tha

t wer

e de

signe

d to

ope

rate

usin

g th

e pr

inci

ples

of e

lect

rom

agne

tic

indu

ctio

n.

11.1

– E

lect

rom

agne

tic

indu

ctio

n

Nat

ure

of sc

ienc

e:

Expe

rimen

tatio

n: In

183

1 M

icha

el F

arad

ay, u

sing

prim

itive

equ

ipm

ent,

obse

rved

a m

inut

e pu

lse

of c

urre

nt in

one

coi

l of w

ire o

nly

whe

n th

e cu

rren

t in

a se

cond

coi

l of w

ire

was

switc

hed

on o

r off

but n

othi

ng w

hile

a c

onst

ant c

urre

nt w

as e

stab

lishe

d. F

arad

ay’s

obse

rvat

ion

of th

ese

smal

l tra

nsie

nt c

urre

nts l

ed h

im to

per

form

exp

erim

ents

that

le

d to

his

law

of e

lect

rom

agne

tic in

duct

ion.

(1.8

)

Und

erst

andi

ngs:

Elec

trom

otiv

e fo

rce

(em

f)

Mag

netic

flux

and

mag

netic

flux

link

age

Fara

day’

s law

of i

nduc

tion

Lenz

’s la

w

App

licat

ions

and

skill

s:

Des

crib

ing

the

prod

uctio

n of

an

indu

ced

emf b

y a

chan

ging

mag

netic

flux

an

d w

ithin

a u

nifo

rm m

agne

tic fi

eld

Solv

ing

prob

lem

s inv

olvi

ng m

agne

tic fl

ux, m

agne

tic fl

ux li

nkag

e an

d

Fara

day’

s law

Expl

aini

ng L

enz’s

law

thro

ugh

the

cons

erva

tion

of e

nerg

y

Theo

ry o

f kno

wle

dge:

Term

inol

ogy

used

in e

lect

rom

agne

tic fi

eld

theo

ry is

ext

ensiv

e an

d ca

n co

nfus

e pe

ople

who

are

not

dire

ctly

invo

lved

. Wha

t effe

ct c

an la

ck o

f cla

rity

in

term

inol

ogy

have

on

com

mun

icat

ing

scie

ntifi

c co

ncep

ts to

the

publ

ic?

Uti

lizat

ion:

Appl

icat

ions

of e

lect

rom

agne

tic in

duct

ion

can

be fo

und

in m

any

plac

es

incl

udin

g tr

ansf

orm

ers,

elec

trom

agne

tic b

raki

ng, g

eoph

ones

use

d in

se

ismol

ogy,

and

met

al d

etec

tors

Aim

s: Aim

2: t

he si

mpl

e pr

inci

ples

of e

lect

rom

agne

tic in

duct

ion

are

a po

wer

ful

aspe

ct o

f the

phy

sicis

t’s o

r tec

hnol

ogis

t’s a

rmou

ry w

hen

desig

ning

syst

ems

that

tran

sfer

ene

rgy

from

one

form

to a

noth

er

Topi

c 11

: Ele

ctro

mag

netic

indu

ctio

n 16

hou

rs

Addi

tiona

l hig

her l

evel

Topic 11: Electromagnetic induction

Physics guide 85

11.1

– E

lect

rom

agne

tic

indu

ctio

n

Gui

danc

e:

Qua

ntita

tive

trea

tmen

ts w

ill b

e ex

pect

ed fo

r str

aigh

t con

duct

ors m

ovin

g at

rig

ht a

ngle

s to

mag

netic

fiel

ds a

nd re

ctan

gula

r coi

ls m

ovin

g in

and

out

of

field

s and

rota

ting

in fi

elds

Qua

litat

ive

trea

tmen

ts o

nly

will

be

expe

cted

for f

ixed

coi

ls in

a c

hang

ing

mag

netic

fiel

d an

d ac

gen

erat

ors

Dat

a bo

okle

t ref

eren

ce:

BAco

sΦ

θ=

Nt

εΦ

=−

∆ ∆

ℓBv

ε=

ℓBv

Nε

=


Physics guide86

Esse

ntia

l ide

a: G

ener

atio

n an

d tr

ansm

issio

n of

alte

rnat

ing

curre

nt (a

c) e

lect

ricity

has

tran

sfor

med

the

wor

ld.

11.2

– P

ower

gen

erat

ion

and

tran

smis

sion

Nat

ure

of sc

ienc

e:

Bias

: In

the

late

19t

h ce

ntur

y Ed

ison

was

a p

ropo

nent

of d

irect

cur

rent

ele

ctric

al e

nerg

y tr

ansm

issio

n w

hile

Wes

tingh

ouse

and

Tes

la fa

vour

ed a

ltern

atin

g cu

rren

t tr

ansm

issio

n. T

he so

cal

led

“bat

tle o

f cur

rent

s” h

ad a

sign

ifica

nt im

pact

on

toda

y’s s

ocie

ty. (

3.5)

Und

erst

andi

ngs:

Alte

rnat

ing

curr

ent (

ac) g

ener

ator

sAv

erag

e po

wer

and

root

mea

n sq

uare

(rm

s) v

alue

s of c

urre

nt a

nd v

olta

geTr

ansf

orm

ers

Dio

de b

ridge

sH

alf-w

ave

and

full-

wav

e re

ctifi

catio

nA

pplic

atio

ns a

nd sk

ills:

Expl

aini

ng th

e op

erat

ion

of a

bas

ic a

c ge

nera

tor,

incl

udin

g th

e ef

fect

of

chan

ging

the

gene

rato

r fre

quen

cySo

lvin

g pr

oble

ms i

nvol

ving

the

aver

age

pow

er in

an

ac c

ircui

tSo

lvin

g pr

oble

ms i

nvol

ving

step

-up

and

step

-dow

n tr

ansf

orm

ers

Des

crib

ing

the

use

of tr

ansf

orm

ers i

n ac

ele

ctric

al p

ower

dis

trib

utio

nIn

vest

igat

ing

a di

ode

brid

ge re

ctifi

catio

n ci

rcui

t exp

erim

enta

llyQ

ualit

ativ

ely

desc

ribin

g th

e ef

fect

of a

ddin

g a

capa

cito

r to

a di

ode

brid

ge

rect

ifica

tion

circ

uit

Gui

danc

e:

Calc

ulat

ions

will

be

rest

ricte

d to

idea

l tra

nsfo

rmer

s but

stud

ents

shou

ld b

e aw

are

of so

me

of th

e re

ason

s why

real

tran

sfor

mer

s are

not

idea

l (fo

r exa

mpl

e: fl

ux

leak

age,

joul

e he

atin

g, e

ddy

curre

nt h

eatin

g, m

agne

tic h

yste

resis

)

Proo

f of t

he re

latio

nshi

p be

twee

n th

e pe

ak a

nd rm

s val

ues w

ill n

ot b

e ex

pect

ed

Inte

rnat

iona

l-min

dedn

ess:

The

abili

ty to

mai

ntai

n a

relia

ble

pow

er g

rid h

as b

een

the

aim

of a

ll go

vern

men

ts si

nce

the

wid

espr

ead

use

of e

lect

ricity

star

ted

Theo

ry o

f kno

wle

dge:

Ther

e is

cont

inue

d de

bate

of t

he e

ffect

of e

lect

rom

agne

tic w

aves

on

th

e he

alth

of h

uman

s, es

peci

ally

chi

ldre

n. Is

it ju

stifi

able

to m

ake

use

of

scie

ntifi

c ad

vanc

es e

ven

if w

e do

not

kno

w w

hat t

heir

long

-ter

m

cons

eque

nces

may

be?

Aim

s: Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

cons

truc

tion

of a

ba

sic a

c ge

nera

tor;

inve

stig

atio

n of

var

iatio

n of

inpu

t and

out

put c

oils

on a

tr

ansf

orm

er; o

bser

ving

Whe

atst

one

and

Wie

n br

idge

circ

uits

Aim

7: c

onst

ruct

ion

and

obse

rvat

ion

of th

e ad

just

men

ts m

ade

in v

ery

larg

e el

ectr

icity

dis

trib

utio

n sy

stem

s are

bes

t car

ried

out u

sing

com

pute

r-mod

ellin

g so

ftw

are

and

web

sites

Aim

9: p

ower

tran

smiss

ion

is m

odel

led

usin

g pe

rfec

tly e

ffic

ient

syst

ems

but n

o su

ch sy

stem

trul

y ex

ists

. Alth

ough

the

mod

el is

impe

rfec

t, it

rend

ers

the

max

imum

pow

er tr

ansm

issio

n. R

ecog

nitio

n of

, and

acc

ount

ing

for,

the

diffe

renc

es b

etw

een

the

“per

fect

” sys

tem

and

the

prac

tical

syst

em is

one

of

the

mai

n fu

nctio

ns o

f pro

fess

iona

l sci

entis

ts


Physics guide 87

11.2

– P

ower

gen

erat

ion

and

tran

smis

sion

Dat

a bo

okle

t ref

eren

ce:

II 2

rms

0=

VV 2

rms

0=

RV I

V I0 0

rms

rms

==

PIV

max

00

=

PIV

1 20

0=

N NI I

p s

p s

s p

ε ε=

=


Physics guide88

Esse

ntia

l ide

a: C

apac

itors

can

be

used

to st

ore

elec

trica

l ene

rgy

for l

ater

use

.

11.3

– C

apac

itan

ce

Nat

ure

of sc

ienc

e:

Rela

tions

hips

: Exa

mpl

es o

f exp

onen

tial g

row

th a

nd d

ecay

per

vade

the

who

le o

f sci

ence

. It i

s a c

lear

exa

mpl

e of

the

way

that

scie

ntis

ts u

se m

athe

mat

ics t

o m

odel

real

ity.

This

topi

c ca

n be

use

d to

cre

ate

links

bet

wee

n ph

ysic

s top

ics b

ut a

lso

to u

ses i

n ch

emis

try,

bio

logy

, med

icin

e an

d ec

onom

ics.

(3.1)

Und

erst

andi

ngs:

Capa

cita

nce

Die

lect

ric m

ater

ials

Capa

cito

rs in

serie

s and

par

alle

l

Resis

tor-

capa

cito

r (RC

) ser

ies c

ircui

ts

Tim

e co

nsta

nt

App

licat

ions

and

skill

s:

Des

crib

ing

the

effe

ct o

f diff

eren

t die

lect

ric m

ater

ials

on c

apac

itanc

e

Solv

ing

prob

lem

s inv

olvi

ng p

aral

lel-p

late

cap

acito

rs

Inve

stig

atin

g co

mbi

natio

ns o

f cap

acito

rs in

serie

s or p

aral

lel c

ircui

ts

Det

erm

inin

g th

e en

ergy

stor

ed in

a c

harg

ed c

apac

itor

Des

crib

ing

the

natu

re o

f the

exp

onen

tial d

isch

arge

of a

cap

acito

r

Solv

ing

prob

lem

s inv

olvi

ng th

e di

scha

rge

of a

cap

acito

r thr

ough

a fi

xed

resis

tor

Solv

ing

prob

lem

s inv

olvi

ng th

e tim

e co

nsta

nt o

f an

RC c

ircui

t for

cha

rge,

vo

ltage

and

cur

rent

Inte

rnat

iona

l-min

dedn

ess:

Ligh

tnin

g is

a ph

enom

enon

that

has

fasc

inat

ed p

hysic

ists

from

Plin

y th

roug

h N

ewto

n to

Fra

nklin

. The

cha

rged

clo

uds f

orm

one

pla

te o

f a c

apac

itor w

ith

othe

r clo

uds o

r Ear

th fo

rmin

g th

e se

cond

pla

te. T

he fr

eque

ncy

of li

ghtn

ing

strik

es v

arie

s glo

bally

, bei

ng p

artic

ular

ly p

reva

lent

in e

quat

oria

l reg

ions

. The

im

pact

of l

ight

ning

strik

es is

sign

ifica

nt, w

ith m

any

hum

ans a

nd a

nim

als b

eing

ki

lled

annu

ally

and

hug

e fin

anci

al c

osts

to in

dust

ry fr

om d

amag

e to

bui

ldin

gs,

com

mun

icat

ion

and

pow

er tr

ansm

issio

n sy

stem

s, an

d de

lays

or t

he n

eed

to

rero

ute

air t

rans

port

.

Uti

lizat

ion:

The

char

ge a

nd d

isch

arge

of c

apac

itors

obe

ys ru

les t

hat h

ave

para

llels

in o

ther

br

anch

es o

f phy

sics i

nclu

ding

radi

oact

ivity

(see

Phy

sics s

ub-t

opic

7.1)

Aim

s: Aim

3: t

he tr

eatm

ent o

f exp

onen

tial g

row

th a

nd d

ecay

by

grap

hica

l and

al

gebr

aic

met

hods

offe

rs b

oth

the

visu

al a

nd ri

goro

us a

ppro

ach

so o

ften

ch

arac

teris

tic o

f sci

ence

and

tech

nolo

gy

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

inve

stig

atin

g ba

sic

RC c

ircui

ts; u

sing

a ca

paci

tor i

n a

brid

ge c

ircui

t; ex

amin

ing

othe

r typ

es o

f ca

paci

tors

; ver

ifyin

g tim

e co

nsta

nt


Physics guide 89

11.3

– C

apac

itan

ce

Gui

danc

e:

Onl

y sin

gle

para

llel-p

late

cap

acito

rs p

rovi

ding

a u

nifo

rm e

lect

ric fi

eld,

in se

ries

with

a lo

ad, n

eed

to b

e co

nsid

ered

(edg

e ef

fect

will

be

negl

ecte

d)

Prob

lem

s inv

olvi

ng th

e di

scha

rge

of c

apac

itors

thro

ugh

fixed

resis

tors

nee

d to

be

trea

ted

both

gra

phic

ally

and

alg

ebra

ical

ly

Prob

lem

s inv

olvi

ng th

e ch

argi

ng o

f a c

apac

itor w

ill o

nly

be tr

eate

d gr

aphi

cally

Der

ivat

ion

of th

e ch

arge

, vol

tage

and

cur

rent

equ

atio

ns a

s a fu

nctio

n of

tim

e is

not r

equi

red

Dat

a bo

okle

t ref

eren

ce:

Cq V

=

!C

CC

para

llel

12

=+

+

11

1

12

CC

Cse

ries

=+

+!

CA d

ε=

ECV1 2

2=

RCτ

=

qq

et

0=

τ−

IIe

t

0=

τ−

VV

et

0=

τ−

Physics guide90

Esse

ntia

l ide

a: T

he m

icro

scop

ic q

uant

um w

orld

offe

rs a

rang

e of

phe

nom

ena,

the

inte

rpre

tatio

n an

d ex

plan

atio

n of

whi

ch re

quire

new

idea

s and

con

cept

s not

foun

d in

the

clas

sical

wor

ld.

12.1

– T

he in

tera

ctio

n of

mat

ter w

ith

radi

atio

n

Nat

ure

of sc

ienc

e:

Obs

erva

tions

: Muc

h of

the

wor

k to

war

ds a

qua

ntum

theo

ry o

f ato

ms w

as g

uide

d by

the

need

to e

xpla

in th

e ob

serv

ed p

atte

rns i

n at

omic

spec

tra.

The

firs

t qua

ntum

mod

el

of m

atte

r is t

he B

ohr m

odel

for h

ydro

gen.

(1.8

)

Para

digm

shift

: The

acc

epta

nce

of th

e w

ave–

part

icle

dua

lity

para

dox

for l

ight

and

par

ticle

s req

uire

d sc

ient

ists

in m

any

field

s to

view

rese

arch

from

new

per

spec

tives

. (2.

3)

Und

erst

andi

ngs:

Phot

ons

The

phot

oele

ctric

effe

ct

Mat

ter w

aves

Pair

prod

uctio

n an

d pa

ir an

nihi

latio

n

Qua

ntiz

atio

n of

ang

ular

mom

entu

m in

the

Bohr

mod

el fo

r hyd

roge

n

The

wav

e fu

nctio

n

The

unce

rtai

nty

prin

cipl

e fo

r ene

rgy

and

time

and

posit

ion

and

mom

entu

m

Tunn

ellin

g, p

oten

tial b

arrie

r and

fact

ors a

ffect

ing

tunn

ellin

g pr

obab

ility

Theo

ry o

f kno

wle

dge:

The

dual

ity o

f mat

ter a

nd tu

nnel

ling

are

case

s whe

re th

e la

ws o

f cla

ssic

al

phys

ics a

re v

iola

ted.

To

wha

t ext

ent h

ave

adva

nces

in te

chno

logy

ena

bled

pa

radi

gm sh

ifts i

n sc

ienc

e?

Uti

lizat

ion:

The

elec

tron

mic

rosc

ope

and

the

tunn

ellin

g el

ectr

on m

icro

scop

e re

ly o

n th

e fin

ding

s fro

m st

udie

s in

quan

tum

phy

sics

Prob

abili

ty is

trea

ted

in a

mat

hem

atic

al se

nse

in M

athe

mat

ical

stud

ies S

L su

b-to

pics

3.6

–3.7

Topi

c 12

: Qua

ntum

and

nuc

lear

phy

sics

16 h

ours

Addi

tiona

l hig

her l

evel

Topic 12: Quantum and nuclear physics

Physics guide 91

12.1

– T

he in

tera

ctio

n of

mat

ter w

ith

radi

atio

n

App

licat

ions

and

skill

s:

Disc

ussin

g th

e ph

otoe

lect

ric e

ffect

exp

erim

ent a

nd e

xpla

inin

g w

hich

feat

ures

of

the

expe

rimen

t can

not b

e ex

plai

ned

by th

e cl

assic

al w

ave

theo

ry o

f lig

ht

Solv

ing

phot

oele

ctric

pro

blem

s bot

h gr

aphi

cally

and

alg

ebra

ical

ly

Disc

ussin

g ex

perim

enta

l evi

denc

e fo

r mat

ter w

aves

, inc

ludi

ng a

n ex

perim

ent

in w

hich

the

wav

e na

ture

of e

lect

rons

is e

vide

nt

Stat

ing

orde

r of m

agni

tude

est

imat

es fr

om th

e un

cert

aint

y pr

inci

ple

Gui

danc

e:

The

orde

r of m

agni

tude

est

imat

es fr

om th

e un

cert

aint

y pr

inci

ple

may

incl

ude

(but

is n

ot li

mite

d to

) est

imat

es o

f the

ene

rgy

of th

e gr

ound

stat

e of

an

atom

, th

e im

poss

ibili

ty o

f an

elec

tron

exi

stin

g w

ithin

a n

ucle

us, a

nd th

e lif

etim

e of

an

ele

ctro

n in

an

exci

ted

ener

gy st

ate

Tunn

ellin

g to

be

trea

ted

qual

itativ

ely

usin

g th

e id

ea o

f con

tinui

ty o

f wav

e fu

nctio

ns

Dat

a bo

okle

t ref

eren

ce:

Ehf

=

Ehf

max

Φ=

−

En

eV13

.6 2=

−

mvr

nh 2π=

Pr

V(

)2

=Ψ

∆

xp

h 4π∆

∆≥

Et

h 4π∆

∆≥

Aim

s: Aim

1: s

tudy

of q

uant

um p

heno

men

a in

trod

uces

stud

ents

to a

n ex

citin

g ne

w

wor

ld th

at is

not

exp

erie

nced

at t

he m

acro

scop

ic le

vel.

The

stud

y of

tunn

elin

g is

a no

vel p

heno

men

on n

ot o

bser

ved

in m

acro

scop

ic p

hysic

s.

Aim

6: t

he p

hoto

elec

tric

effe

ct c

an b

e in

vest

igat

ed u

sing

LED

s

Aim

9: t

he B

ohr m

odel

is v

ery

succ

essf

ul w

ith h

ydro

gen

but n

ot o

f any

use

for

othe

r ele

men

ts


Physics guide92

Esse

ntia

l ide

a: T

he id

ea o

f dis

cret

enes

s tha

t we

met

in th

e at

omic

wor

ld c

ontin

ues t

o ex

ist i

n th

e nu

clea

r wor

ld a

s wel

l.

12.2

– N

ucle

ar p

hysi

cs

Nat

ure

of sc

ienc

e:

Theo

retic

al a

dvan

ces a

nd in

spira

tion:

Pro

gres

s in

atom

ic, n

ucle

ar a

nd p

artic

le p

hysic

s oft

en c

ame

from

theo

retic

al a

dvan

ces a

nd st

roke

s of i

nspi

ratio

n.

Adva

nces

in in

stru

men

tatio

n: N

ew w

ays o

f det

ectin

g su

bato

mic

par

ticle

s due

to a

dvan

ces i

n el

ectr

onic

tech

nolo

gy w

ere

also

cru

cial

.

Mod

ern

com

putin

g po

wer

: Fin

ally

, the

ana

lysis

of t

he d

ata

gath

ered

in m

oder

n pa

rtic

le d

etec

tors

in p

artic

le a

ccel

erat

or e

xper

imen

ts w

ould

be

impo

ssib

le w

ithou

t mod

ern

com

putin

g po

wer

. (1.

8)

Und

erst

andi

ngs:

Ruth

erfo

rd sc

atte

ring

and

nucl

ear r

adiu

s

Nuc

lear

ene

rgy

leve

ls

The

neut

rino

The

law

of r

adio

activ

e de

cay

and

the

deca

y co

nsta

nt

App

licat

ions

and

skill

s:

Des

crib

ing

a sc

atte

ring

expe

rimen

t inc

ludi

ng lo

catio

n of

min

imum

inte

nsity

fo

r the

diff

ract

ed p

artic

les b

ased

on

thei

r de

Brog

lie w

avel

engt

h

Expl

aini

ng d

evia

tions

from

Rut

herf

ord

scat

terin

g in

hig

h en

ergy

exp

erim

ents

Des

crib

ing

expe

rimen

tal e

vide

nce

for n

ucle

ar e

nerg

y le

vels

Solv

ing

prob

lem

s inv

olvi

ng th

e ra

dioa

ctiv

e de

cay

law

for a

rbitr

ary

time

inte

rval

s

Expl

aini

ng th

e m

etho

ds fo

r mea

surin

g sh

ort a

nd lo

ng h

alf-l

ives

Theo

ry o

f kno

wle

dge:

Muc

h of

the

know

ledg

e ab

out s

ubat

omic

par

ticle

s is b

ased

on

the

mod

els o

ne

uses

to in

terp

ret t

he d

ata

from

exp

erim

ents

. How

can

we

be su

re th

at w

e ar

e di

scov

erin

g an

“ind

epen

dent

trut

h” n

ot in

fluen

ced

by o

ur m

odel

s? Is

ther

e su

ch a

thin

g as

a si

ngle

trut

h?

Uti

lizat

ion:

Know

ledg

e of

radi

oact

ivity

, rad

ioac

tive

subs

tanc

es a

nd th

e ra

dioa

ctiv

e de

cay

law

are

cru

cial

in m

oder

n nu

clea

r med

icin

e (s

ee P

hysic

s opt

ion

sub-

topi

c C.

4)

Aim

s: Aim

2: d

etec

tion

of th

e ne

utrin

o de

mon

stra

tes t

he c

ontin

uing

gro

win

g bo

dy

of k

now

ledg

e sc

ient

ists

are

gat

herin

g in

this

area

of s

tudy


Physics guide 93

12.2

– N

ucle

ar p

hysi

cs

Gui

danc

e:

Stud

ents

shou

ld b

e aw

are

that

nuc

lear

den

sitie

s are

app

roxi

mat

ely

the

sam

e fo

r all

nucl

ei a

nd th

at th

e on

ly m

acro

scop

ic o

bjec

ts w

ith th

e sa

me

dens

ity a

s nu

clei

are

neu

tron

star

s

The

smal

l ang

le a

ppro

xim

atio

n is

usua

lly n

ot a

ppro

pria

te to

use

to d

eter

min

e th

e lo

catio

n of

the

min

imum

inte

nsity

Dat

a bo

okle

t ref

eren

ce:

•R

RA

01/

3=

•N

Ne

t0

=λ−

•A

Ne

t0

λ=

λ−

•D

sinθ

λ≈

Physics guide94

Esse

ntia

l ide

a: E

inst

ein’

s st

udy

of e

lect

rom

agne

tism

reve

aled

inco

nsis

tenc

ies

betw

een

the

theo

ry o

f Max

wel

l and

New

ton‘

s m

echa

nics

. He

reco

gniz

ed th

at b

oth

theo

ries

coul

d no

t be

reco

ncile

d an

d so

cho

osin

g to

trus

t Max

wel

l’s th

eory

of e

lect

rom

agne

tism

he

was

forc

ed to

cha

nge

long

-che

rishe

d id

eas a

bout

spac

e an

d tim

e in

mec

hani

cs.

A.1

– T

he b

egin

ning

s of r

elat

ivit

y

Nat

ure

of sc

ienc

e:

Para

digm

shift

: The

fund

amen

tal f

act t

hat t

he sp

eed

of li

ght i

s con

stan

t for

all

iner

tial o

bser

vers

has

far-r

each

ing

cons

eque

nces

abo

ut o

ur u

nder

stan

ding

of s

pace

and

tim

e.

Idea

s abo

ut sp

ace

and

time

that

wen

t unc

halle

nged

for m

ore

than

2,0

00 y

ears

wer

e sh

own

to b

e fa

lse.

The

ext

ensio

n of

the

prin

cipl

e of

rela

tivity

to a

ccel

erat

ed fr

ames

of

refe

renc

e le

ads t

o th

e re

volu

tiona

ry id

ea o

f gen

eral

rela

tivity

that

the

mas

s and

ene

rgy

that

spac

etim

e co

ntai

ns d

eter

min

es th

e ge

omet

ry o

f spa

cetim

e. (2

.3)

Und

erst

andi

ngs:

Refe

renc

e fr

ames

Gal

ilean

rela

tivity

and

New

ton’

s pos

tula

tes c

once

rnin

g tim

e an

d sp

ace

Max

wel

l and

the

cons

tanc

y of

the

spee

d of

ligh

t

Forc

es o

n a

char

ge o

r cur

rent

App

licat

ions

and

skill

s:

Usin

g th

e G

alile

an tr

ansf

orm

atio

n eq

uatio

ns

Det

erm

inin

g w

heth

er a

forc

e on

a c

harg

e or

cur

rent

is e

lect

ric o

r mag

netic

in a

gi

ven

fram

e of

refe

renc

e

Det

erm

inin

g th

e na

ture

of t

he fi

elds

obs

erve

d by

diff

eren

t obs

erve

rs

Theo

ry o

f kno

wle

dge:

Whe

n sc

ient

ists

cla

im a

new

dire

ctio

n in

thin

king

requ

ires a

par

adig

m sh

ift in

ho

w w

e ob

serv

e th

e un

iver

se, h

ow d

o w

e en

sure

thei

r cla

ims a

re v

alid

?

Aim

s: Aim

3: t

his s

ub-t

opic

is th

e co

rner

ston

e of

dev

elop

men

ts th

at fo

llow

ed in

re

lativ

ity a

nd m

oder

n ph

ysic

s

Core

topi

cs

15 h

ours

Opt

ion

A: R

elat

ivity

Core topics

Physics guide 95

A.1

– T

he b

egin

ning

s of r

elat

ivit

y

Gui

danc

e:

Max

wel

l’s e

quat

ions

do

not n

eed

to b

e de

scrib

ed

Qua

litat

ive

trea

tmen

t of e

lect

ric a

nd m

agne

tic fi

elds

as m

easu

red

by

obse

rver

s in

rela

tive

mot

ion.

Exa

mpl

es w

ill in

clud

e a

char

ge m

ovin

g in

a

mag

netic

fiel

d or

two

char

ged

part

icle

s mov

ing

with

par

alle

l vel

ociti

es.

Stud

ents

will

be

aske

d to

ana

lyse

thes

e m

otio

ns fr

om th

e po

int o

f vie

w o

f ob

serv

ers a

t res

t with

resp

ect t

o th

e pa

rtic

les a

nd o

bser

vers

at r

est w

ith

resp

ect t

o th

e m

agne

tic fi

eld.

Dat

a bo

okle

t ref

eren

ce:

xx

vt′=

−u

uv

′=−

Core topics

Physics guide96

Esse

ntia

l ide

a: O

bser

vers

in re

lativ

e un

iform

mot

ion

disa

gree

on

the

num

eric

al v

alue

s of

spa

ce a

nd ti

me

coor

dina

tes

for e

vent

s, bu

t agr

ee w

ith th

e nu

mer

ical

val

ue o

f th

e sp

eed

of li

ght i

n a

vacu

um. T

he L

oren

tz tr

ansf

orm

atio

n eq

uatio

ns re

late

the

valu

es in

one

refe

renc

e fr

ame

to th

ose

in a

noth

er. T

hese

equ

atio

ns re

plac

e th

e G

alile

an

tran

sfor

mat

ion

equa

tions

that

fail

for s

peed

s clo

se to

that

of l

ight

.

A.2

– L

oren

tz tr

ansf

orm

atio

ns

Nat

ure

of sc

ienc

e:

Pure

scie

nce:

Ein

stei

n ba

sed

his t

heor

y of

rela

tivity

on

two

post

ulat

es a

nd d

educ

ed th

e re

st b

y m

athe

mat

ical

ana

lysis

. The

firs

t pos

tula

te in

tegr

ates

all

of th

e la

ws o

f phy

sics

incl

udin

g th

e la

ws o

f ele

ctro

mag

netis

m, n

ot o

nly

New

ton’

s law

s of m

echa

nics

. (1.

2)

Und

erst

andi

ngs:

The

two

post

ulat

es o

f spe

cial

rela

tivity

Cloc

k sy

nchr

oniz

atio

n

The

Lore

ntz

tran

sfor

mat

ions

Velo

city

add

ition

Inva

riant

qua

ntiti

es (s

pace

time

inte

rval

, pro

per t

ime,

pro

per l

engt

h an

d

rest

mas

s)

Tim

e di

latio

n

Leng

th c

ontr

actio

n

The

muo

n de

cay

expe

rimen

t

App

licat

ions

and

skill

s:

Usin

g th

e Lo

rent

z tr

ansf

orm

atio

ns to

des

crib

e ho

w d

iffer

ent m

easu

rem

ents

of

spac

e an

d tim

e by

two

obse

rver

s can

be

conv

erte

d in

to th

e m

easu

rem

ents

ob

serv

ed in

eith

er fr

ame

of re

fere

nce

Usin

g th

e Lo

rent

z tr

ansf

orm

atio

n eq

uatio

ns to

det

erm

ine

the

posit

ion

and

time

coor

dina

tes o

f var

ious

eve

nts

Usin

g th

e Lo

rent

z tr

ansf

orm

atio

n eq

uatio

ns to

show

that

if tw

o ev

ents

are

sim

ulta

neou

s for

one

obs

erve

r but

hap

pen

at d

iffer

ent p

oint

s in

spac

e, th

en

the

even

ts a

re n

ot si

mul

tane

ous f

or a

n ob

serv

er in

a d

iffer

ent r

efer

ence

fram

e

Solv

ing

prob

lem

s inv

olvi

ng v

eloc

ity a

dditi

on

Der

ivin

g th

e tim

e di

latio

n an

d le

ngth

con

trac

tion

equa

tions

usin

g th

e Lo

rent

z eq

uatio

ns

Uti

lizat

ion:

Onc

e a

very

eso

teric

par

t of p

hysic

s, re

lativ

ity id

eas a

bout

spac

e an

d tim

e ar

e ne

eded

in o

rder

to p

rodu

ce a

ccur

ate

glob

al p

ositi

onin

g sy

stem

s (G

PS)

Aim

s: Aim

2: t

he L

oren

tz tr

ansf

orm

atio

n fo

rmul

ae p

rovi

de a

con

siste

nt b

ody

of

know

ledg

e th

at c

an b

e us

ed to

com

pare

the

desc

riptio

n of

mot

ion

by o

ne

obse

rver

to th

e de

scrip

tion

of a

noth

er o

bser

ver i

n re

lativ

e m

otio

n to

th

e fir

st

Aim

3: t

hese

form

ulae

can

be

appl

ied

to a

var

ied

set o

f con

ditio

ns a

nd

situa

tions

Aim

9: t

he in

trod

uctio

n of

rela

tivity

pus

hed

the

limits

of G

alile

an th

ough

ts o

n sp

ace

and

mot

ion

Core topics

Physics guide 97

A.2

– L

oren

tz tr

ansf

orm

atio

ns

Solv

ing

prob

lem

s inv

olvi

ng ti

me

dila

tion

and

leng

th c

ontr

actio

nSo

lvin

g pr

oble

ms i

nvol

ving

the

muo

n de

cay

expe

rimen

tG

uida

nce:

Prob

lem

s will

be

limite

d to

one

dim

ensio

nD

eriv

atio

n of

the

Lore

ntz

tran

sfor

mat

ion

equa

tions

will

not

be

exam

ined

Muo

n de

cay

expe

rimen

ts c

an b

e us

ed a

s evi

denc

e fo

r bot

h tim

e di

latio

n an

d le

ngth

con

trac

tion

Dat

a bo

okle

t ref

eren

ce:

v c

1

12 2

γ=

−

xx

vtx

xv

t(

);(

)γ

γ′=

−∆

′=∆

−∆

′ =−

⎛ ⎝⎜⎞ ⎠⎟

′ =−

⎛ ⎝⎜⎞ ⎠⎟

tt

vx ct

tv

xc

γγ

22

;∆∆

∆

uu

v uv c1

2

′=− −

tt 0

γ∆

=∆

LL 0 γ

= ctx

ctx

()

()

()

()

22

22

′−

′=

−

Core topics

Physics guide98

Esse

ntia

l ide

a: S

pace

time

diag

ram

s are

a v

ery

clea

r and

illu

stra

tive

way

to sh

ow g

raph

ical

ly h

ow d

iffer

ent o

bser

vers

in re

lativ

e m

otio

n to

eac

h ot

her h

ave

mea

sure

men

ts th

at

diffe

r fro

m e

ach

othe

r.

A.3

– S

pace

tim

e di

agra

ms

Nat

ure

of sc

ienc

e:

Visu

aliz

atio

n of

mod

els:

The

visu

aliz

atio

n of

the

desc

riptio

n of

eve

nts i

n te

rms o

f spa

cetim

e di

agra

ms i

s an

enor

mou

s adv

ance

in u

nder

stan

ding

the

conc

ept o

f spa

cetim

e. (1

.10)

Und

erst

andi

ngs:

Spac

etim

e di

agra

ms

Wor

ldlin

es

The

twin

par

adox

App

licat

ions

and

skill

s:

Repr

esen

ting

even

ts o

n a

spac

etim

e di

agra

m a

s poi

nts

Repr

esen

ting

the

posit

ions

of a

mov

ing

part

icle

on

a sp

acet

ime

diag

ram

by

a cu

rve

(the

wor

ldlin

e)

Repr

esen

ting

mor

e th

an o

ne in

ertia

l ref

eren

ce fr

ame

on th

e sa

me

spac

etim

e di

agra

m

Det

erm

inin

g th

e an

gle

betw

een

a w

orld

line

for s

peci

fic sp

eed

and

the

time

axis

on a

spac

etim

e di

agra

m

Solv

ing

prob

lem

s on

simul

tane

ity a

nd k

inem

atic

s usin

g sp

acet

ime

diag

ram

s

Repr

esen

ting

time

dila

tion

and

leng

th c

ontr

actio

n on

spac

etim

e di

agra

ms

Des

crib

ing

the

twin

par

adox

Reso

lvin

g of

the

twin

par

adox

thro

ugh

spac

etim

e di

agra

ms

Theo

ry o

f kno

wle

dge:

Can

para

doxe

s be

solv

ed b

y re

ason

alo

ne, o

r do

they

requ

ire th

e ut

iliza

tion

of

othe

r way

s of k

now

ing?

Aim

s: Aim

4: s

pace

time

diag

ram

s allo

w o

ne to

ana

lyse

pro

blem

s in

rela

tivity

m

ore

relia

bly

Core topics

Physics guide 99

A.3

– S

pace

tim

e di

agra

ms

Gui

danc

e:

Exam

inat

ion

ques

tions

will

refe

r to

spac

etim

e di

agra

ms;

thes

e ar

e al

so k

now

n as

Min

kow

ski d

iagr

ams

Qua

ntita

tive

ques

tions

invo

lvin

g sp

acet

ime

diag

ram

s will

be

limite

d to

co

nsta

nt v

eloc

ity

Spac

etim

e di

agra

ms c

an h

ave

t or c

t on

the

vert

ical

axi

s

Exam

inat

ion

ques

tions

may

use

uni

ts in

whi

ch c

= 1

Dat

a bo

okle

t ref

eren

ce:

cta

n1

θ υ

= ⎛ ⎝⎜

⎞ ⎠⎟−

Physics guide100

Esse

ntia

l ide

a: T

he re

lativ

ity o

f spa

ce a

nd ti

me

requ

ires n

ew d

efin

ition

s for

ene

rgy

and

mom

entu

m in

ord

er to

pre

serv

e th

e co

nser

ved

natu

re o

f the

se la

ws.

A.4

– R

elat

ivis

tic

mec

hani

cs

Nat

ure

of sc

ienc

e:

Para

digm

shift

: Ein

stei

n re

aliz

ed th

at th

e la

w o

f con

serv

atio

n of

mom

entu

m c

ould

not

be

mai

ntai

ned

as a

law

of p

hysic

s. H

e th

eref

ore

dedu

ced

that

in o

rder

for m

omen

tum

to

be

cons

erve

d un

der a

ll co

nditi

ons,

the

defin

ition

of m

omen

tum

had

to c

hang

e an

d al

ong

with

it th

e de

finiti

ons o

f oth

er m

echa

nics

qua

ntiti

es su

ch a

s kin

etic

ene

rgy

and

tota

l ene

rgy

of a

par

ticle

. Thi

s was

a m

ajor

par

adig

m sh

ift. (

2.3)

Und

erst

andi

ngs:

Tota

l ene

rgy

and

rest

ene

rgy

Rela

tivis

tic m

omen

tum

Part

icle

acc

eler

atio

n

Elec

tric

cha

rge

as a

n in

varia

nt q

uant

ity

Phot

ons

MeV

c–2 a

s the

uni

t of m

ass a

nd M

eV c–1

as t

he u

nit o

f mom

entu

m

App

licat

ions

and

skill

s:

Des

crib

ing

the

law

s of c

onse

rvat

ion

of m

omen

tum

and

con

serv

atio

n of

en

ergy

with

in sp

ecia

l rel

ativ

ity

Det

erm

inin

g th

e po

tent

ial d

iffer

ence

nec

essa

ry to

acc

eler

ate

a pa

rtic

le to

a

give

n sp

eed

or e

nerg

y

Solv

ing

prob

lem

s inv

olvi

ng re

lativ

istic

ene

rgy

and

mom

entu

m c

onse

rvat

ion

in c

ollis

ions

and

par

ticle

dec

ays

Theo

ry o

f kno

wle

dge:

In w

hat w

ays d

o la

ws i

n th

e na

tura

l sci

ence

s diff

er fr

om la

ws i

n ec

onom

ics?

Uti

lizat

ion:

The

law

s of r

elat

ivis

tic m

echa

nics

are

rout

inel

y us

ed in

ord

er to

man

age

the

oper

atio

n of

nuc

lear

pow

er p

lant

s, pa

rtic

le a

ccel

erat

ors a

nd p

artic

le d

etec

tors

Aim

s: Aim

4: r

elat

ivis

tic m

echa

nics

synt

hesiz

es k

now

ledg

e on

the

beha

viou

r of

mat

ter a

t spe

eds c

lose

to th

e sp

eed

of li

ght

Aim

9: t

he th

eory

of r

elat

ivity

impo

ses o

ne se

vere

lim

itatio

n: n

othi

ng c

an

exce

ed th

e sp

eed

of li

ght

Addi

tiona

l hig

her l

evel

opt

ion

topi

cs

10 h

ours

Opt

ion

A: R

elat

ivity

Additional higher level option topics

Physics guide 101

A.4

– R

elat

ivis

tic

mec

hani

cs

Gui

danc

e:

Appl

icat

ions

will

invo

lve

rela

tivis

tic d

ecay

s suc

h as

cal

cula

ting

the

wav

elen

gths

of p

hoto

ns in

the

deca

y of

a m

ovin

g pi

on [

2]

oπ

γ→

The

sym

bol m

0 ref

ers t

o th

e in

varia

nt re

st m

ass o

f a p

artic

le

The

conc

ept o

f a re

lativ

istic

mas

s tha

t var

ies w

ith sp

eed

will

not

be

used

Prob

lem

s will

be

limite

d to

one

dim

ensio

n

Dat

a bo

okle

t ref

eren

ce:

Em

c 02

γ=

Em

c0

02

=

Em

c(

1)K

02

γ=

−

pm

0γ

υ=

Ep

cm

c2

22

024

=+

qVE K

=∆


Physics guide102

Esse

ntia

l ide

a: G

ener

al re

lativ

ity is

app

lied

to b

ring

toge

ther

fund

amen

tal c

once

pts o

f mas

s, sp

ace

and

time

in o

rder

to d

escr

ibe

the

fate

of t

he u

nive

rse.

A.5

– G

ener

al re

lati

vity

Nat

ure

of sc

ienc

e:

Crea

tive

and

criti

cal t

hink

ing:

Ein

stei

n’s g

reat

ach

ieve

men

t, th

e ge

nera

l the

ory

of re

lativ

ity, i

s bas

ed o

n in

tuiti

on, c

reat

ive

thin

king

and

imag

inat

ion,

nam

ely

to c

onne

ct th

e ge

omet

ry o

f spa

cetim

e (th

roug

h its

cur

vatu

re) t

o th

e m

ass a

nd e

nerg

y co

nten

t of s

pace

time.

For

yea

rs it

was

thou

ght t

hat n

othi

ng c

ould

esc

ape

a bl

ack

hole

and

this

is tr

ue b

ut o

nly

for c

lass

ical

bla

ck h

oles

. Whe

n qu

antu

m th

eory

is ta

ken

into

acc

ount

a b

lack

hol

e ra

diat

es li

ke a

bla

ck b

ody.

Thi

s une

xpec

ted

resu

lt re

veal

ed o

ther

equ

ally

un

expe

cted

con

nect

ions

bet

wee

n bl

ack

hole

s and

ther

mod

ynam

ics.

(1.4

)

Und

erst

andi

ngs:

The

equi

vale

nce

prin

cipl

e

The

bend

ing

of li

ght

Gra

vita

tiona

l red

shift

and

the

Poun

d–Re

bka–

Snid

er e

xper

imen

t

Schw

arzs

child

bla

ck h

oles

Even

t hor

izon

s

Tim

e di

latio

n ne

ar a

bla

ck h

ole

Appl

icat

ions

of g

ener

al re

lativ

ity to

the

univ

erse

as a

who

le

App

licat

ions

and

skill

s:

Usin

g th

e eq

uiva

lenc

e pr

inci

ple

to d

educ

e an

d ex

plai

n lig

ht b

endi

ng n

ear m

assiv

e ob

ject

s

Usin

g th

e eq

uiva

lenc

e pr

inci

ple

to d

educ

e an

d ex

plai

n gr

avita

tiona

l tim

e di

latio

n

Calc

ulat

ing

grav

itatio

nal f

requ

ency

shift

s

Des

crib

ing

an e

xper

imen

t in

whi

ch g

ravi

tatio

nal r

edsh

ift is

obs

erve

d an

d m

easu

red

Calc

ulat

ing

the

Schw

arzs

child

radi

us o

f a b

lack

hol

e

Appl

ying

the

form

ula

for g

ravi

tatio

nal t

ime

dila

tion

near

the

even

t hor

izon

of a

bl

ack

hole

Theo

ry o

f kno

wle

dge:

Alth

ough

Ein

stei

n se

lf-de

scrib

ed th

e co

smol

ogic

al c

onst

ant a

s his

“gre

ates

t bl

unde

r”, th

e 20

11 N

obel

Priz

e w

as w

on b

y sc

ient

ists

who

had

pro

ved

it to

be

valid

thro

ugh

thei

r stu

dies

on

dark

ene

rgy.

Wha

t oth

er e

xam

ples

are

ther

e of

in

itial

ly d

oubt

ed c

laim

s bei

ng p

rove

n co

rrec

t lat

er in

his

tory

?

Uti

lizat

ion:

For t

he g

loba

l pos

ition

ing

syst

em to

be

so a

ccur

ate,

gen

eral

rela

tivity

mus

t be

take

n in

to a

ccou

nt in

cal

cula

ting

the

deta

ils o

f the

sate

llite

’s or

bit

The

deve

lopm

ent o

f the

gen

eral

theo

ry o

f rel

ativ

ity h

as b

een

used

to e

xpla

in

the

very

larg

e-sc

ale

beha

viou

r of t

he u

nive

rse

as a

who

le w

ith fa

r-rea

chin

g im

plic

atio

ns a

bout

the

futu

re d

evel

opm

ent a

nd fa

te o

f the

uni

vers

e

Aim

s: Aim

2: t

he g

ener

al th

eory

of r

elat

ivity

is a

gre

at sy

nthe

sis o

f ide

as th

at a

re re

quire

d to

des

crib

e th

e la

rge-

scal

e st

ruct

ure

of th

e un

iver

se

Aim

9: it

mus

t be

appr

ecia

ted

that

the

mag

nific

ent N

ewto

nian

stru

ctur

e ha

d se

rious

limita

tions

whe

n it

cam

e to

the

desc

riptio

n of

ver

y de

taile

d as

pect

s of

plan

etar

y m

otio

n


Physics guide 103

A.5

– G

ener

al re

lati

vity

Gui

danc

e:

Stud

ents

shou

ld re

cogn

ize

the

equi

vale

nce

prin

cipl

e in

term

s of a

ccel

erat

ing

refe

renc

e fr

ames

and

free

ly fa

lling

fram

es

Dat

a bo

okle

t ref

eren

ce:

f fg

hc2

∆=

∆

RGM c2

s2

= tt R r

1

0

S

∆=

∆ −

Physics guide104

Esse

ntia

l ide

a: T

he b

asic

law

s of

mec

hani

cs h

ave

an e

xten

sion

whe

n eq

uiva

lent

prin

cipl

es a

re a

pplie

d to

rota

tion.

Act

ual o

bjec

ts h

ave

dim

ensi

ons

and

they

requ

ire

the

expa

nsio

n of

the

poin

t par

ticle

mod

el to

con

side

r the

pos

sibi

lity

of d

iffer

ent p

oint

s on

an

obje

ct h

avin

g di

ffer

ent s

tate

s of

mot

ion

and/

or d

iffer

ent v

eloc

ities

.

B.1

– Ri

gid

bodi

es a

nd ro

tati

onal

dyn

amic

s

Nat

ure

of sc

ienc

e:

Mod

ellin

g: T

he u

se o

f mod

els h

as d

iffer

ent p

urpo

ses a

nd h

as a

llow

ed sc

ient

ists

to id

entif

y, si

mpl

ify a

nd a

naly

se a

pro

blem

with

in a

giv

en c

onte

xt to

tack

le it

succ

essf

ully

. Th

e ex

tens

ion

of th

e po

int p

artic

le m

odel

to a

ctua

lly c

onsid

er th

e di

men

sions

of a

n ob

ject

led

to m

any

grou

ndbr

eaki

ng d

evel

opm

ents

in e

ngin

eerin

g. (1

.2)

Und

erst

andi

ngs:

Torq

ue

Mom

ent o

f ine

rtia

Rota

tiona

l and

tran

slatio

nal e

quili

briu

m

Angu

lar a

ccel

erat

ion

Equa

tions

of r

otat

iona

l mot

ion

for u

nifo

rm a

ngul

ar a

ccel

erat

ion

New

ton’

s sec

ond

law

app

lied

to a

ngul

ar m

otio

n

Cons

erva

tion

of a

ngul

ar m

omen

tum

App

licat

ions

and

skill

s:

Calc

ulat

ing

torq

ue fo

r sin

gle

forc

es a

nd co

uple

s

Solv

ing

prob

lem

s inv

olvi

ng m

omen

t of i

nert

ia, t

orqu

e an

d an

gula

r acc

eler

atio

n

Solv

ing

prob

lem

s in

whi

ch o

bjec

ts a

re in

bot

h ro

tatio

nal a

nd tr

ansla

tiona

l eq

uilib

rium

Theo

ry o

f kno

wle

dge:

Mod

els a

re a

lway

s val

id w

ithin

a c

onte

xt a

nd th

ey a

re m

odifi

ed, e

xpan

ded

or re

plac

ed w

hen

that

con

text

is a

ltere

d or

con

sider

ed d

iffer

ently

. Are

ther

e ex

ampl

es o

f unc

hang

ing

mod

els i

n th

e na

tura

l sci

ence

s or i

n an

y ot

her a

reas

of

kno

wle

dge?

Uti

lizat

ion:

Stru

ctur

al d

esig

n an

d ci

vil e

ngin

eerin

g re

ly o

n th

e kn

owle

dge

of h

ow o

bjec

ts

can

mov

e in

all

situa

tions

Aim

s: Aim

7: t

echn

olog

y ha

s allo

wed

for c

ompu

ter s

imul

atio

ns th

at a

ccur

atel

y m

odel

th

e co

mpl

icat

ed o

utco

mes

of a

ctio

ns o

n bo

dies

Core

topi

cs

15 h

ours

Opt

ion

B: E

ngin

eerin

g ph

ysic

s

Core topics

Physics guide 105

B.1

– Ri

gid

bodi

es a

nd ro

tati

onal

dyn

amic

s

Solv

ing

prob

lem

s usin

g ro

tatio

nal q

uant

ities

ana

logo

us to

linea

r qua

ntiti

es

Sket

chin

g an

d in

terp

retin

g gr

aphs

of r

otat

iona

l mot

ion

Solv

ing

prob

lem

s inv

olvi

ng ro

lling

with

out s

lippi

ng

Gui

danc

e:

Anal

ysis

will

be

limite

d to

bas

ic g

eom

etric

shap

es

The

equa

tion

for t

he m

omen

t of i

nert

ia o

f a sp

ecifi

c sh

ape

will

be

prov

ided

w

hen

nece

ssar

y

Gra

phs w

ill b

e lim

ited

to a

ngul

ar d

ispla

cem

ent–

time,

ang

ular

vel

ocity

–tim

e an

d to

rque

–tim

e

Dat

a bo

okle

t ref

eren

ce:

Frsin

Γθ

=

Im

r2=

Σ IΓ

α=

f2

ωπ

=

tf

iω

ωα

=+

2f2

i2ω

ωα

θ=

+

tt

1 2i

2θ

ωα

=+

LIω

= EI

1 2K

2ro

tω

=

Core topics

Physics guide106 Essential idea: The first law of thermodynamics relates the change in internal energy of a system to the energy transferred and the work done. The entropy of the universe

tends to a maximum.


Nature of science:

Variety of perspectives: With three alternative and equivalent statements of the second law of thermodynamics, this area of physics demonstrates the collaboration and testing involved in confirming abstract notions such as this. (4.1)

Understandings:

The first law of thermodynamics

The second law of thermodynamics

Entropy

Cyclic processes and pV diagrams

Isovolumetric, isobaric, isothermal and adiabatic processes

Carnot cycle

Thermal efficiency


Describing the first law of thermodynamics as a statement of conservation of energy

Explaining sign convention used when stating the first law of thermodynamics a

Q U W= ∆ +

Solving problems involving the first law of thermodynamics

Describing the second law of thermodynamics in Clausius form, Kelvin form and as a consequence of entropy


The development of this topic was the subject of intense debate between scientists of many countries in the 19th century

Utilization:

This work leads directly to the concept of the heat engines that play such a large role in modern society

The possibility of the heat death of the universe is based on ever-increasing entropy

Chemistry of entropy (see Chemistry sub-topic 15.2)

Aims:

Aim 5: development of the second law demonstrates the collaboration involved in scientific pursuits

Aim 10: the relationships and similarities between scientific disciplines are particularly apparent here

Core topics

Physics guide107


Describing examples of processes in terms of entropy change

Solving problems involving entropy changes

Sketching and interpreting cyclic processes

Solving problems for adiabatic processes for monatomic gases using pV

53 = constant

Solving problems involving thermal efficiency

Guidance:

If cycles other than the Carnot cycle are used quantitatively, full details will be provided

Only graphical analysis will be required for determination of work done on a pV diagram when pressure is not constant


Q U W= ∆ +

U nRT32

=

SQ

T∆ = ∆

pV53 = constant (for monatomic gases)

W p V= ∆

useful work doneenergy input

η =

TT

1Carnotcold

hot

η = −

Physics guide108

Esse

ntia

l ide

a: F

luid

s ca

nnot

be

mod

elle

d as

poi

nt p

artic

les.

Thei

r dis

tingu

isha

ble

resp

onse

to c

ompr

essi

on fr

om s

olid

s cr

eate

s a

set o

f cha

ract

eris

tics

that

requ

ire a

n in

-de

pth

stud

y.

B.3

– Fl

uids

and

flui

d dy

nam

ics

Nat

ure

of sc

ienc

e:

Hum

an u

nder

stan

ding

s: U

nder

stan

ding

and

mod

ellin

g flu

id fl

ow h

as b

een

impo

rtan

t in

man

y te

chno

logi

cal d

evel

opm

ents

such

as d

esig

ns o

f tur

bine

s, ae

rody

nam

ics o

f ca

rs a

nd a

ircra

ft, a

nd m

easu

rem

ent o

f blo

od fl

ow. (

1.1)

Und

erst

andi

ngs:

Den

sity

and

pres

sure

Buoy

ancy

and

Arc

him

edes

’ prin

cipl

e

Pasc

al’s

prin

cipl

e

Hyd

rost

atic

equ

ilibr

ium

The

idea

l flu

id

Stre

amlin

es

The

cont

inui

ty e

quat

ion

The

Bern

oulli

equ

atio

n an

d th

e Be

rnou

lli e

ffect

Stok

es’ l

aw a

nd v

isco

sity

Lam

inar

and

turb

ulen

t flo

w a

nd th

e Re

ynol

ds n

umbe

r

App

licat

ions

and

skill

s:

Det

erm

inin

g bu

oyan

cy fo

rces

usin

g Ar

chim

edes

’ prin

cipl

e

Solv

ing

prob

lem

s inv

olvi

ng p

ress

ure,

den

sity

and

Pasc

al’s

prin

cipl

e

Solv

ing

prob

lem

s usin

g th

e Be

rnou

lli e

quat

ion

and

the

cont

inui

ty e

quat

ion

Inte

rnat

iona

l-min

dedn

ess:

Wat

er so

urce

s for

dam

s and

irrig

atio

n re

ly o

n th

e kn

owle

dge

of fl

uid

flow

. Th

ese

reso

urce

s can

cro

ss n

atio

nal b

ound

arie

s lea

ding

to sh

arin

g of

wat

er o

r di

sput

es o

ver o

wne

rshi

p an

d us

e.

Theo

ry o

f kno

wle

dge:

The

myt

holo

gy b

ehin

d th

e an

ecdo

te o

f Arc

him

edes

’ “Eu

reka

!” m

omen

t of

disc

over

y de

mon

stra

tes o

ne o

f the

man

y w

ays s

cien

tific

kno

wle

dge

has b

een

tran

smitt

ed th

roug

hout

the

ages

. Wha

t rol

e ca

n m

ytho

logy

and

ane

cdot

es

play

in p

assin

g on

scie

ntifi

c kn

owle

dge?

Wha

t rol

e m

ight

they

pla

y in

pas

sing

on sc

ient

ific

know

ledg

e w

ithin

indi

geno

us k

now

ledg

e sy

stem

s?

Uti

lizat

ion:

Hyd

roel

ectr

ic p

ower

stat

ions

Aero

dyna

mic

des

ign

of a

ircra

ft a

nd v

ehic

les

Flui

d m

echa

nics

is e

ssen

tial i

n un

ders

tand

ing

bloo

d flo

w in

art

erie

s

Biom

echa

nics

(see

Spo

rts,

exer

cise

and

hea

lth sc

ienc

e SL

sub-

topi

c 4.

3)

Addi

tiona

l hig

her l

evel

opt

ion

topi

cs

10 h

ours

Opt

ion

B: E

ngin

eerin

g ph

ysic

s


Physics guide 109

B.3

– Fl

uids

and

flui

d dy

nam

ics

Expl

aini

ng si

tuat

ions

invo

lvin

g th

e Be

rnou

lli e

ffect

Des

crib

ing

the

fric

tiona

l dra

g fo

rce

exer

ted

on sm

all s

pher

ical

obj

ects

in

lam

inar

flui

d flo

w

Solv

ing

prob

lem

s inv

olvi

ng S

toke

s’ la

w

Det

erm

inin

g th

e Re

ynol

ds n

umbe

r in

simpl

e sit

uatio

ns

Gui

danc

e:

Idea

l flu

ids w

ill b

e ta

ken

to m

ean

fluid

s tha

t are

inco

mpr

essib

le a

nd n

on-

visc

ous a

nd h

ave

stea

dy fl

ows

Appl

icat

ions

of t

he B

erno

ulli

equa

tion

will

invo

lve

(but

not

be

limite

d to

) flo

w

out o

f a c

onta

iner

, det

erm

inin

g th

e sp

eed

of a

pla

ne (p

itot t

ubes

), an

d ve

ntur

i tu

bes

Proo

f of t

he B

erno

ulli

equa

tion

will

not

be

requ

ired

for e

xam

inat

ion

purp

oses

Lam

inar

and

turb

ulen

t flo

w w

ill o

nly

be c

onsid

ered

in si

mpl

e sit

uatio

ns

Valu

es o

f R

103

< w

ill b

e ta

ken

to re

pres

ent

cond

ition

s for

lam

inar

flow

Dat

a bo

okle

t ref

eren

ce:

BV

gf

fρ

=

ρ=

+P

Pgd

0f

Avco

nsta

nt= v

gzp

1 2co

nsta

nt2

ρρ

++

=

Frv

6D

πη=

Rvr

ρ η=

Aim

s: Aim

2: f

luid

dyn

amic

s is a

n es

sent

ial p

art o

f any

uni

vers

ity p

hysic

s or e

ngin

eerin

g co

urse

Aim

7: t

he co

mpl

exity

of f

luid

dyn

amic

s mak

es it

an

idea

l top

ic to

be

visu

alize

d th

roug

h co

mpu

ter s

oftw

are


Physics guide110

Esse

ntia

l ide

a: In

the

real

wor

ld, d

ampi

ng o

ccur

s in

osci

llato

rs a

nd h

as im

plic

atio

ns th

at n

eed

to b

e co

nsid

ered

.

B.4

– Fo

rced

vib

rati

ons a

nd re

sona

nce

Nat

ure

of sc

ienc

e:

Risk

ass

essm

ent:

The

idea

s of r

eson

ance

and

forc

ed o

scill

atio

n ha

ve a

pplic

atio

n in

man

y ar

eas o

f eng

inee

ring

rang

ing

from

ele

ctric

al o

scill

atio

n to

the

safe

des

ign

of c

ivil

stru

ctur

es. I

n la

rge-

scal

e ci

vil s

truc

ture

s, m

odel

ling

all p

ossib

le e

ffect

s is e

ssen

tial b

efor

e co

nstr

uctio

n. (4

.8)

Und

erst

andi

ngs:

Nat

ural

freq

uenc

y of

vib

ratio

nQ

fact

or a

nd d

ampi

ngPe

riodi

c st

imul

us a

nd th

e dr

ivin

g fre

quen

cyRe

sona

nce

App

licat

ions

and

skill

s:

Qua

litat

ivel

y an

d qu

antit

ativ

ely

desc

ribin

g ex

ampl

es o

f und

er-,

over

- and

criti

cally

-da

mpe

d os

cilla

tions

Inte

rnat

iona

l-min

dedn

ess:

Com

mun

icat

ion

thro

ugh

radi

o an

d te

levi

sion

signa

ls is

base

d on

reso

nanc

e of

th

e br

oadc

ast s

igna

ls

Uti

lizat

ion:

Scie

nce

and

tech

nolo

gy m

eet h

ead-

on w

hen

the

real

beh

avio

ur o

f dam

ped

osci

llatin

g sy

stem

s is m

odel

led


Physics guide 111

B.4

– Fo

rced

vib

rati

ons a

nd re

sona

nce

Gra

phic

ally

des

crib

ing

the

varia

tion

of th

e am

plitu

de o

f vib

ratio

n w

ith d

rivin

g fre

quen

cy o

f an

obje

ct c

lose

to it

s nat

ural

freq

uenc

y of

vib

ratio

n

Des

crib

ing

the

phas

e re

latio

nshi

p be

twee

n dr

ivin

g fre

quen

cy a

nd fo

rced

os

cilla

tions

Solv

ing

prob

lem

s inv

olvi

ng Q

fact

or

Des

crib

ing

the

usef

ul a

nd d

estr

uctiv

e ef

fect

s of r

eson

ance

Gui

danc

e:

Onl

y am

plitu

de re

sona

nce

is re

quire

d

Dat

a bo

okle

t ref

eren

ce:

Q2

ener

gyst

ored

ener

gydi

ssip

ated

perc

ycle

π=

Q2

reso

nant

frequ

ency

ener

gyst

ored

pow

erlo

ssπ

=×

×

Aim

s: Aim

6: e

xper

imen

ts co

uld

incl

ude

(but

are

not

limite

d to

): obs

erva

tion

of sa

nd o

n a

vibr

atin

g su

rface

of v

aryi

ng fr

eque

ncie

s; in

vest

igat

ion

of th

e ef

fect

of i

ncre

asin

g da

mpi

ng o

n an

osc

illat

ing

syst

em, s

uch

as a

tuni

ng fo

rk; o

bser

ving

the

use

of a

dr

ivin

g fre

quen

cy o

n fo

rced

osc

illat

ions

Aim

7: t

o in

vest

igat

e th

e us

e of

reso

nanc

e in

ele

ctric

al ci

rcui

ts, a

tom

s/m

olec

ules

, or

with

radi

o/te

levi

sion

com

mun

icat

ions

is b

est a

chie

ved

thro

ugh

soft

war

e m

odel

ling

exam

ples

Physics guide112

Esse

ntia

l ide

a: T

he p

rogr

ess o

f a w

ave

can

be m

odel

led

via

the

ray

or th

e w

avef

ront

. The

cha

nge

in w

ave

spee

d w

hen

mov

ing

betw

een

med

ia c

hang

es th

e sh

ape

of th

e w

ave.

C.1

– In

trod

ucti

on to

imag

ing

Nat

ure

of sc

ienc

e:

Ded

uctiv

e lo

gic:

The

use

of v

irtua

l im

ages

is e

ssen

tial f

or o

ur a

naly

sis o

f len

ses a

nd m

irror

s. (1

.6)

Und

erst

andi

ngs:

Thin

lens

es

Conv

ergi

ng a

nd d

iver

ging

lens

es

Conv

ergi

ng a

nd d

iver

ging

mirr

ors

Ray

diag

ram

s

Real

and

virt

ual i

mag

es

Line

ar a

nd a

ngul

ar m

agni

ficat

ion

Sphe

rical

and

chr

omat

ic a

berr

atio

ns

App

licat

ions

and

skill

s:

Des

crib

ing

how

a c

urve

d tr

ansp

aren

t int

erfa

ce m

odifi

es th

e sh

ape

of a

n in

cide

nt w

avef

ront

Iden

tifyi

ng th

e pr

inci

pal a

xis,

foca

l poi

nt a

nd fo

cal l

engt

h of

a si

mpl

e co

nver

ging

or d

iver

ging

lens

on

a sc

aled

dia

gram

Solv

ing

prob

lem

s inv

olvi

ng n

ot m

ore

than

two

lens

es b

y co

nstr

uctin

g sc

aled

ra

y di

agra

ms

Inte

rnat

iona

l-min

dedn

ess:

Opt

ics i

s an

anci

ent s

tudy

enc

ompa

ssin

g de

velo

pmen

t mad

e in

the

early

G

reco

-Rom

an a

nd m

edie

val I

slam

ic w

orld

s

Theo

ry o

f kno

wle

dge:

Coul

d sig

n co

nven

tion,

usin

g th

e sy

mbo

ls of

pos

itive

and

neg

ativ

e,

emot

iona

lly in

fluen

ce sc

ient

ists

?

Uti

lizat

ion:

Mic

rosc

opes

and

tele

scop

es

Eyeg

lass

es a

nd c

onta

ct le

nses

Aim

s: Aim

3: t

he th

eorie

s of o

ptic

s, or

igin

atin

g w

ith h

uman

cur

iosit

y of

our

ow

n se

nses

, con

tinue

to b

e of

gre

at v

alue

in le

adin

g to

new

and

use

ful t

echn

olog

y

Aim

6: e

xper

imen

ts c

ould

incl

ude

(but

are

not

lim

ited

to):

mag

nific

atio

n de

term

inat

ion

usin

g an

opt

ical

ben

ch; i

nves

tigat

ing

real

and

virt

ual i

mag

es

form

ed b

y le

nses

; obs

ervi

ng a

berr

atio

ns

Core

topi

cs

15 h

ours

Opt

ion

C: Im

agin

g

Core topics

Physics guide 113

C.1

– In

trod

ucti

on to

imag

ing

Solv

ing

prob

lem

s inv

olvi

ng n

ot m

ore

than

two

curv

ed m

irror

s by

cons

truc

ting

scal

ed ra

y di

agra

ms

Solv

ing

prob

lem

s inv

olvi

ng th

e th

in le

ns e

quat

ion,

line

ar m

agni

ficat

ion

and

angu

lar m

agni

ficat

ion

Expl

aini

ng sp

heric

al a

nd c

hrom

atic

abe

rrat

ions

and

des

crib

ing

way

s to

redu

ce

thei

r effe

cts o

n im

ages

Gui

danc

e:

Stud

ents

shou

ld tr

eat t

he p

assa

ge o

f lig

ht th

roug

h le

nses

from

the

stan

dpoi

nt

of b

oth

rays

and

wav

efro

nts

Curv

ed m

irror

s are

lim

ited

to sp

heric

al a

nd p

arab

olic

con

verg

ing

mirr

ors a

nd

sphe

rical

div

ergi

ng m

irror

s

Onl

y th

in le

nses

are

to b

e co

nsid

ered

in th

is to

pic

The

lens

-mak

er’s

form

ula

is no

t req

uire

d

Sign

con

vent

ion

used

in e

xam

inat

ions

will

be

base

d on

real

bei

ng p

ositi

ve

(the

“rea

l-is-

posit

ive”

con

vent

ion)

Dat

a bo

okle

t ref

eren

ce:

fv

u1

11

=+

Pf1

=

mh h

v ui o

==

−

Mi oθ θ

=

MD f

MD f

near

poi

ntin

finity

=

+=

1;

Core topics

Physics guide114

Esse

ntia

l ide

a: O

ptic

al m

icro

scop

es a

nd te

lesc

opes

util

ize

simila

r phy

sical

pro

pert

ies o

f len

ses a

nd m

irror

s. An

alys

is of

the

univ

erse

is p

erfo

rmed

bot

h op

tical

ly a

nd b

y us

ing

radi

o te

lesc

opes

to in

vest

igat

e di

ffere

nt re

gion

s of t

he e

lect

rom

agne

tic sp

ectr

um.

C.2

– Im

agin

g in

stru

men

tati

on

Nat

ure

of sc

ienc

e:

Impr

oved

inst

rum

enta

tion:

The

opt

ical

tele

scop

e ha

s bee

n in

use

for o

ver 5

00 y

ears

. It h

as e

nabl

ed h

uman

kind

to o

bser

ve a

nd h

ypot

hesiz

e ab

out t

he u

nive

rse.

Mor

e re

cent

ly, r

adio

tele

scop

es h

ave

been

dev

elop

ed to

inve

stig

ate

the

elec

trom

agne

tic ra

diat

ion

beyo

nd th

e vi

sible

regi

on. T

eles

cope

s (bo

th v

isual

and

radi

o) a

re n

ow p

lace

d aw

ay fr

om th

e Ea

rth’

s sur

face

to a

void

the

imag

e de

grad

atio

n ca

used

by

the

atm

osph

ere,

whi

le c

orre

ctiv

e op

tics a

re u

sed

to e

nhan

ce im

ages

col

lect

ed a

t the

Ear

th’s

surf

ace.

Man

y sa

telli

tes h

ave

been

laun

ched

with

sens

ors c

apab

le o

f rec

ordi

ng v

ast a

mou

nts o

f dat

a in

the

infr

ared

, ultr

avio

let,

X-ra

y an

d ot

her e

lect

rom

agne

tic sp

ectr

um

rang

es. (

1.8)

Und

erst

andi

ngs:

Opt

ical

com

poun

d m

icro

scop

es

Sim

ple

optic

al a

stro

nom

ical

refr

actin

g te

lesc

opes

Sim

ple

optic

al a

stro

nom

ical

refle

ctin

g te

lesc

opes

Sing

le-d

ish ra

dio

tele

scop

es

Radi

o in

terf

erom

etry

tele

scop

es

Sate

llite

-bor

ne te

lesc

opes

App

licat

ions

and

skill

s:

Cons

truc

ting

and

inte

rpre

ting

ray

diag

ram

s of o

ptic

al c

ompo

und

mic

rosc

opes

at

nor

mal

adj

ustm

ent

Solv

ing

prob

lem

s inv

olvi

ng th

e an

gula

r mag

nific

atio

n an

d re

solu

tion

of

optic

al c

ompo

und

mic

rosc

opes

Inve

stig

atin

g th

e op

tical

com

poun

d m

icro

scop

e ex

perim

enta

lly

Cons

truc

ting

or c

ompl

etin

g ra

y di

agra

ms o

f sim

ple

optic

al a

stro

nom

ical

re

frac

ting

tele

scop

es a

t nor

mal

adj

ustm

ent

Inte

rnat

iona

l-min

dedn

ess:

The

use

of th

e ra

dio

inte

rfer

omet

ry te

lesc

ope

cros

ses c

ultu

res w

ith

colla

bora

tion

betw

een

scie

ntis

ts fr

om m

any

coun

trie

s to

prod

uce

arra

ys o

f in

terf

erom

eter

s tha

t spa

n th

e co

ntin

ents

Theo

ry o

f kno

wle

dge:

How

ever

adv

ance

d th

e te

chno

logy

, mic

rosc

opes

and

tele

scop

es a

lway

s in

volv

e se

nse

perc

eptio

n. C

an te

chno

logy

be

used

effe

ctiv

ely

to e

xten

d or

co

rrec

t our

sens

es?

Uti

lizat

ion:

Cell

obse

rvat

ion

(see

Bio

logy

sub-

topi

c 1.

2)

The

info

rmat

ion

that

the

astr

onom

ical

tele

scop

es g

athe

r con

tinue

s to

allo

w u

s to

impr

ove

our u

nder

stan

ding

of t

he u

nive

rse

Reso

lutio

n is

cove

red

for o

ther

sour

ces i

n Ph

ysic

s sub

-top

ic 9

.4

Core topics

Physics guide 115

C.2

– Im

agin

g in

stru

men

tati

on

Solv

ing

prob

lem

s inv

olvi

ng th

e an

gula

r mag

nific

atio

n of

sim

ple

optic

al

astr

onom

ical

tele

scop

es

Inve

stig

atin

g th

e pe

rfor

man

ce o

f a si

mpl

e op

tical

ast

rono

mic

al re

frac

ting

tele

scop

e ex

perim

enta

lly

Des

crib

ing

the

com

para

tive

perf

orm

ance

of E

arth

-bas

ed te

lesc

opes

and

sa

telli

te-b

orne

tele

scop

es

Gui

danc

e:

Sim

ple

optic

al a

stro

nom

ical

refle

ctin

g te

lesc

ope

desig

n is

limite

d to

N

ewto

nian

and

Cas

segr

ain

mou

ntin

g

Radi

o in

terf

erom

eter

tele

scop

es sh

ould

be

appr

oxim

ated

as a

dish

of d

iam

eter

eq

ual t

o th

e m

axim

um se

para

tion

of th

e an

tenn

ae

Radi

o in

terfe

rom

etry

tele

scop

es re

fer t

o ar

ray

tele

scop

es

Dat

a bo

okle

t ref

eren

ce:

=M

f fo e

Aim

s: Aim

3: i

mag

es fr

om m

icro

scop

es a

nd te

lesc

opes

bot

h in

the

scho

ol la

bora

tory

an

d ob

tain

ed v

ia th

e in

tern

et e

nabl

e st

uden

ts to

app

ly th

eir k

now

ledg

e of

th

ese

tech

niqu

es

Aim

5: r

esea

rch

astr

onom

y an

d as

trop

hysic

s is a

n ex

ampl

e of

the

need

fo

r col

labo

ratio

n be

twee

n te

ams o

f sci

entis

ts fr

om d

iffer

ent c

ount

ries a

nd

cont

inen

ts

Aim

6: l

ocal

am

ateu

r or p

rofe

ssio

nal a

stro

nom

ical

org

aniz

atio

ns c

an b

e us

eful

fo

r arr

angi

ng d

emon

stra

tions

of t

he n

ight

sky

Core topics

Physics guide116

Esse

ntia

l ide

a: T

otal

inte

rnal

refle

ctio

n al

low

s lig

ht o

r inf

rare

d ra

diat

ion

to tr

avel

alo

ng a

tran

spar

ent f

ibre

. How

ever

, the

per

form

ance

of a

fibr

e ca

n be

deg

rade

d by

di

sper

sion

and

atte

nuat

ion

effe

cts.

C.3

– Fi

bre

opti

cs

Nat

ure

of sc

ienc

e:

Appl

ied

scie

nce:

Adv

ance

s in

com

mun

icat

ion

links

usin

g fib

re o

ptic

s hav

e le

d to

a g

loba

l net

wor

k of

opt

ical

fibr

es th

at h

as tr

ansf

orm

ed g

loba

l com

mun

icat

ions

by

voic

e,

vide

o an

d da

ta. (

1.2)

Und

erst

andi

ngs:

Stru

ctur

e of

opt

ic fi

bres

Step

-inde

x fib

res a

nd g

rade

d-in

dex

fibre

s

Tota

l inte

rnal

refle

ctio

n an

d cr

itica

l ang

le

Wav

egui

de a

nd m

ater

ial d

isper

sion

in o

ptic

fibr

es

Atte

nuat

ion

and

the

deci

bel (

dB) s

cale

App

licat

ions

and

skill

s:

Solv

ing

prob

lem

s inv

olvi

ng to

tal in

tern

al re

flect

ion

and

criti

cal a

ngle

in th

e co

ntex

t of f

ibre

opt

ics

Des

crib

ing

how

wav

egui

de a

nd m

ater

ial d

isper

sion

can

lead

to a

tten

uatio

n an

d ho

w th

is ca

n be

acc

ount

ed fo

r

Solv

ing

prob

lem

s inv

olvi

ng a

tten

uatio

n

Des

crib

ing

the

adva

ntag

es o

f fib

re o

ptic

s ove

r tw

iste

d pa

ir an

d co

axia

l cab

les

Inte

rnat

iona

l-min

dedn

ess:

The

unde

r-sea

opt

ic fi

bres

are

a v

ital p

art o

f the

com

mun

icat

ion

betw

een

cont

inen

ts

Uti

lizat

ion:

Will

a c

omm

unic

atio

n lim

it be

reac

hed

as w

e ca

nnot

mov

e in

form

atio

n fa

ster

th

an th

e sp

eed

of li

ght?

Aim

s: Aim

1: t

his i

s a g

loba

l tec

hnol

ogy

that

em

brac

es a

nd d

rives

incr

ease

s in

com

mun

icat

ion

spee

ds

Aim

9: t

he d

isper

sion

effe

cts i

llust

rate

the

inhe

rent

lim

itatio

ns th

at c

an b

e pa

rt o

f a te

chno

logy

Core topics

Physics guide 117

C.3

– Fi

bre

opti

cs

Gui

danc

e:

Qua

ntita

tive

desc

riptio

ns o

f att

enua

tion

are

requ

ired

and

incl

ude

atte

nuat

ion

per u

nit l

engt

h

The

term

wav

egui

de d

isper

sion

will

be

used

in e

xam

inat

ions

. Wav

egui

de

disp

ersio

n is

som

etim

es k

now

n as

mod

al d

isper

sion.

Dat

a bo

okle

t ref

eren

ce:

nc

1sin

=

I Iat

tenu

atio

n=

10lo

g0

Physics guide118

Esse

ntia

l ide

a: T

he b

ody

can

be im

aged

usin

g ra

diat

ion

gene

rate

d fro

m b

oth

outs

ide

and

insid

e. Im

agin

g ha

s ena

bled

med

ical

pra

ctiti

oner

s to

impr

ove

diag

nosis

with

few

er

inva

sive

proc

edur

es.

C.4

– M

edic

al im

agin

g

Nat

ure

of sc

ienc

e:

Risk

ana

lysis

: The

doc

tor’s

role

is to

min

imiz

e pa

tient

risk

in m

edic

al d

iagn

osis

and

proc

edur

es b

ased

on

an a

sses

smen

t of t

he o

vera

ll be

nefit

to th

e pa

tient

. Arg

umen

ts

invo

lvin

g pr

obab

ility

are

use

d in

con

sider

ing

the

atte

nuat

ion

of ra

diat

ion

tran

smitt

ed th

roug

h th

e bo

dy. (

4.8)

Und

erst

andi

ngs:

Det

ectio

n an

d re

cord

ing

of X

-ray

imag

es in

med

ical

cont

exts

Gen

erat

ion

and

dete

ctio

n of

ultr

asou

nd in

med

ical

cont

exts

Med

ical

imag

ing

tech

niqu

es (m

agne

tic re

sona

nce

imag

ing)

invo

lvin

g nu

clea

r m

agne

tic re

sona

nce

(NM

R)

App

licat

ions

and

skill

s:

Expl

aini

ng fe

atur

es o

f X-ra

y im

agin

g, in

clud

ing

atte

nuat

ion

coef

ficie

nt, h

alf-v

alue

th

ickn

ess,

linea

r/mas

s abs

orpt

ion

coef

ficie

nts a

nd te

chni

ques

for i

mpr

ovem

ents

of

shar

pnes

s and

cont

rast

Solv

ing

X-ra

y at

tenu

atio

n pr

oble

ms

Solv

ing

prob

lem

s inv

olvi

ng u

ltras

ound

aco

ustic

impe

danc

e, sp

eed

of u

ltras

ound

th

roug

h tis

sue

and

air a

nd re

lativ

e in

tens

ity le

vels

Inte

rnat

iona

l-min

dedn

ess:

Ther

e is

cons

tant

dia

logu

e be

twee

n re

sear

ch c

linic

ians

in d

iffer

ent c

ount

ries

to c

omm

unic

ate

new

met

hods

and

trea

tmen

ts fo

r the

goo

d of

pat

ient

s ev

eryw

here

Org

aniz

atio

ns su

ch a

s Méd

ecin

s San

s Fro

ntiè

res p

rovi

de v

alua

ble

med

ical

skill

s in

par

ts o

f the

wor

ld w

here

med

ical

hel

p is

requ

ired

Theo

ry o

f kno

wle

dge:

“It’s

not w

hat y

ou lo

ok a

t tha

t mat

ters

, it’s

wha

t you

see.

” – H

enry

Dav

id

Thor

eau.

To

wha

t ext

ent d

o yo

u ag

ree

with

this

com

men

t on

the

impa

ct o

f fa

ctor

s suc

h as

exp

ecta

tion

on p

erce

ptio

n?

Uti

lizat

ion:

Scan

ning

the

hum

an b

rain

(see

Bio

logy

sub-

topi

c A.

4)

Addi

tiona

l hig

her l

evel

opt

ion

topi

cs

10 h

ours

Opt

ion

C: Im

agin

g

Additional higher level topics

Physics guide 119

C.4

– M

edic

al im

agin

g

Expl

aini

ng fe

atur

es o

f med

ical

ultr

asou

nd te

chni

ques

, incl

udin

g ch

oice

of

frequ

ency

, use

of g

el a

nd th

e di

ffere

nce

betw

een

A an

d B

scan

s

Expl

aini

ng th

e us

e of

gra

dien

t fie

lds i

n N

MR

Expl

aini

ng th

e or

igin

of t

he re

laxa

tion

of p

roto

n sp

in a

nd co

nseq

uent

em

issio

n of

sig

nal in

NM

R

Disc

ussin

g th

e ad

vant

ages

and

disa

dvan

tage

s of u

ltras

ound

and

NM

R sc

anni

ng

met

hods

, incl

udin

g a

simpl

e as

sess

men

t of r

isk in

thes

e m

edic

al p

roce

dure

s

Gui

danc

e:

Stud

ents

will

be

expe

cted

to co

mpu

te fi

nal b

eam

inte

nsity

afte

r pas

sage

thro

ugh

mul

tiple

laye

rs o

f tiss

ue. O

nly

para

llel p

lane

inte

rface

s will

be

treat

ed.

Dat

a bo

okle

t ref

eren

ce:

=L

I I10

log

I1 0

IIe

x0

=µ−

xln

21 2

µ=

Zcρ

=

Aim

s: Aim

4: t

here

are

man

y op

port

uniti

es fo

r stu

dent

s to

anal

yse

and

eval

uate

sc

ient

ific

info

rmat

ion

Aim

8: t

he so

cial

impa

ct o

f the

se sc

ient

ific

tech

niqu

es fo

r the

ben

efit

of

hum

anki

nd c

anno

t be

over

-em

phas

ized

Aim

10:

med

icin

e an

d ph

ysic

s mee

t in

the

hi-t

ech

wor

ld o

f sca

nnin

g an

d tr

eatm

ent.

Mod

ern

doct

ors r

ely

on te

chno

logy

that

aris

es fr

om d

evel

opm

ents

in

the

phys

ical

scie

nces

.

Physics guide120

Esse

ntia

l ide

a: O

ne o

f the

mos

t diff

icul

t pro

blem

s in

ast

rono

my

is c

omin

g to

term

s w

ith th

e va

st d

ista

nces

bet

wee

n st

ars

and

gala

xies

and

dev

isin

g ac

cura

te m

etho

ds fo

r m

easu

ring

them

.

D.1

– S

tella

r qua

ntit

ies

Nat

ure

of sc

ienc

e:

Real

ity: T

he sy

stem

atic

mea

sure

men

t of d

ista

nce

and

brig

htne

ss o

f sta

rs a

nd g

alax

ies h

as le

d to

an

unde

rsta

ndin

g of

the

univ

erse

on

a sc

ale

that

is d

iffic

ult t

o im

agin

e an

d co

mpr

ehen

d. (1

.1)

Und

erst

andi

ngs:

Obj

ects

in th

e un

iver

se

The

natu

re o

f sta

rs

Astr

onom

ical

dis

tanc

es

Stel

lar p

aral

lax

and

its li

mita

tions

Lum

inos

ity a

nd a

ppar

ent b

right

ness

App

licat

ions

and

skill

s:

Iden

tifyi

ng o

bjec

ts in

the

univ

erse

Qua

litat

ivel

y de

scrib

ing

the

equi

libriu

m b

etw

een

pres

sure

and

gra

vita

tion

in

star

s

Usin

g th

e as

tron

omic

al u

nit (

AU),

light

yea

r (ly

) and

par

sec

(pc)

Des

crib

ing

the

met

hod

to d

eter

min

e di

stan

ce to

star

s thr

ough

stel

lar p

aral

lax

Solv

ing

prob

lem

s inv

olvi

ng lu

min

osity

, app

aren

t brig

htne

ss a

nd d

ista

nce

Theo

ry o

f kno

wle

dge:

The

vast

dis

tanc

es b

etw

een

star

s and

gal

axie

s are

diff

icul

t to

com

preh

end

or

imag

ine.

Are

oth

er w

ays o

f kno

win

g m

ore

usef

ul th

an im

agin

atio

n fo

r gai

ning

kn

owle

dge

in a

stro

nom

y?

Uti

lizat

ion:

Sim

ilar p

aral

lax

tech

niqu

es c

an b

e us

ed to

acc

urat

ely

mea

sure

dis

tanc

es h

ere

on E

arth

Aim

s: Aim

1: c

reat

ivity

is re

quire

d to

ana

lyse

obj

ects

that

are

such

vas

t dis

tanc

es

from

us

Aim

6: l

ocal

am

ateu

r or p

rofe

ssio

nal a

stro

nom

ical

org

aniz

atio

ns c

an b

e us

eful

fo

r arr

angi

ng v

iew

ing

even

ings

Aim

9: a

s we

are

able

to o

bser

ve fu

rthe

r int

o th

e un

iver

se, w

e re

ach

the

limits

of

our

cur

rent

tech

nolo

gy to

mak

e ac

cura

te m

easu

rem

ents

Core

topi

cs

15 h

ours

Opt

ion

D: A

stro

phys

ics

Core topics

Physics guide 121

D.1

– S

tella

r qua

ntit

ies

Gui

danc

e:

For t

his c

ours

e, o

bjec

ts in

the

univ

erse

incl

ude

plan

ets,

com

ets,

star

s (sin

gle

and

bina

ry),

plan

etar

y sy

stem

s, co

nste

llatio

ns, s

tella

r clu

ster

s (op

en a

nd

glob

ular

), ne

bula

e, g

alax

ies,

clus

ters

of g

alax

ies a

nd su

per c

lust

ers o

f gal

axie

s

Stud

ents

are

exp

ecte

d to

hav

e an

aw

aren

ess o

f the

vas

t cha

nges

in d

ista

nce

scal

e fro

m p

lane

tary

syst

ems t

hrou

gh to

supe

r clu

ster

s of g

alax

ies a

nd th

e un

iver

se a

s a w

hole

Dat

a bo

okle

t ref

eren

ce:

dp

(par

sec)

1(a

rc–s

econ

d)=

LAT

4σ

=

bL d

42

π=

Core topics

Physics guide122

Esse

ntia

l ide

a: A

sim

ple

diag

ram

that

plo

ts th

e lu

min

osity

ver

sus t

he su

rfac

e te

mpe

ratu

re o

f sta

rs re

veal

s unu

sual

ly d

etai

led

patt

erns

that

hel

p un

ders

tand

the

inne

r wor

king

s of

star

s. St

ars f

ollo

w w

ell-d

efin

ed p

atte

rns f

rom

the

mom

ent t

hey

are

crea

ted

out o

f col

laps

ing

inte

rste

llar g

as, t

o th

eir l

ives

on

the

mai

n se

quen

ce a

nd to

thei

r eve

ntua

l dea

th.

D.2

– S

tella

r cha

ract

eris

tics

and

stel

lar e

volu

tion

Nat

ure

of sc

ienc

e:

Evid

ence

: The

sim

ple

light

spec

tra

of a

gas

on

Eart

h ca

n be

com

pare

d to

the

light

spec

tra

of d

ista

nt st

ars.

This

has a

llow

ed u

s to

dete

rmin

e th

e ve

loci

ty, c

ompo

sitio

n an

d st

ruct

ure

of st

ars a

nd c

onfir

med

hyp

othe

ses a

bout

the

expa

nsio

n of

the

univ

erse

. (1.1

1)

Und

erst

andi

ngs:

Stel

lar s

pect

ra

Her

tzsp

rung

–Rus

sell

(HR)

dia

gram

Mas

s–lu

min

osity

rela

tion

for m

ain

sequ

ence

star

s

Ceph

eid

varia

bles

Stel

lar e

volu

tion

on H

R di

agra

ms

Red

gian

ts, w

hite

dw

arfs

, neu

tron

star

s and

bla

ck h

oles

Chan

dras

ekha

r and

Opp

enhe

imer

–Vol

koff

limits

App

licat

ions

and

skill

s:

Expl

aini

ng h

ow su

rfac

e te

mpe

ratu

re m

ay b

e ob

tain

ed fr

om a

star

’s sp

ectr

um

Expl

aini

ng h

ow th

e ch

emic

al c

ompo

sitio

n of

a st

ar m

ay b

e de

term

ined

from

th

e st

ar’s

spec

trum

Sket

chin

g an

d in

terp

retin

g H

R di

agra

ms

Iden

tifyi

ng th

e m

ain

regi

ons o

f the

HR

diag

ram

and

des

crib

ing

the

mai

n pr

oper

ties o

f sta

rs in

thes

e re

gion

s

Appl

ying

the

mas

s–lu

min

osity

rela

tion

Des

crib

ing

the

reas

on fo

r the

var

iatio

n of

Cep

heid

var

iabl

es

Det

erm

inin

g di

stan

ce u

sing

data

on

Ceph

eid

varia

bles

Sket

chin

g an

d in

terp

retin

g ev

olut

iona

ry p

aths

of s

tars

on

an H

R di

agra

m

Des

crib

ing

the

evol

utio

n of

star

s off

the

mai

n se

quen

ce

Des

crib

ing

the

role

of m

ass i

n st

ella

r evo

lutio

n

Theo

ry o

f kno

wle

dge:

The

info

rmat

ion

reve

aled

thro

ugh

spec

tra

need

s a tr

aine

d m

ind

to b

e in

terp

rete

d. W

hat i

s the

role

of i

nter

pret

atio

n in

gai

ning

kno

wle

dge

in th

e na

tura

l sci

ence

s? H

ow d

oes t

his d

iffer

from

the

role

of i

nter

pret

atio

n in

oth

er

area

s of k

now

ledg

e?

Uti

lizat

ion:

An u

nder

stan

ding

of h

ow si

mila

r sta

rs to

our

Sun

hav

e ag

ed a

nd e

volv

ed

assis

ts in

our

pre

dict

ions

of o

ur fa

te o

n Ea

rth

Aim

s: Aim

4: a

naly

sis o

f sta

r spe

ctra

pro

vide

s man

y op

port

uniti

es fo

r eva

luat

ion

an

d sy

nthe

sis

Aim

6: s

oftw

are-

base

d an

alys

is is

avai

labl

e fo

r stu

dent

s to

part

icip

ate

in

astr

ophy

sics r

esea

rch

Core topics

Physics guide 123

D.2

– S

tella

r cha

ract

eris

tics

and

stel

lar e

volu

tion

Gui

danc

e:

Regi

ons o

f the

HR

diag

ram

are

rest

ricte

d to

the

mai

n se

quen

ce, w

hite

dw

arfs

, re

d gi

ants

, sup

er g

iant

s and

the

inst

abili

ty st

rip (v

aria

ble

star

s), a

s wel

l as l

ines

of

con

stan

t rad

ius

HR

diag

ram

s will

be

labe

lled

with

lum

inos

ity o

n th

e ve

rtic

al a

xis a

nd

tem

pera

ture

on

the

horiz

onta

l axi

s

Onl

y on

e sp

ecifi

c ex

pone

nt (3

.5) w

ill b

e us

ed in

the

mas

s–lu

min

osity

rela

tion

Refe

renc

es to

ele

ctro

n an

d ne

utro

n de

gene

racy

pre

ssur

es n

eed

to b

e m

ade

Dat

a bo

okle

t ref

eren

ce:

λ max

T=

×−

29

103

.m

K

LM

3.5

∝

Core topics

Physics guide124

Esse

ntia

l ide

a: T

he H

ot B

ig B

ang

mod

el is

a th

eory

that

des

crib

es th

e or

igin

and

exp

ansio

n of

the

univ

erse

and

is su

ppor

ted

by e

xten

sive

expe

rimen

tal e

vide

nce.

D.3

– C

osm

olog

y

Nat

ure

of sc

ienc

e:

Occ

am’s

Razo

r: Th

e Bi

g Ba

ng m

odel

was

pur

ely

spec

ulat

ive

until

it w

as c

onfir

med

by

the

disc

over

y of

the

cosm

ic m

icro

wav

e ba

ckgr

ound

radi

atio

n. T

he m

odel

, whi

le

corr

ectly

des

crib

ing

man

y as

pect

s of t

he u

nive

rse

as w

e ob

serv

e it

toda

y, st

ill c

anno

t exp

lain

wha

t hap

pene

d at

tim

e ze

ro. (

2.7)

Und

erst

andi

ngs:

The

Big

Bang

mod

el

Cosm

ic m

icro

wav

e ba

ckgr

ound

(CM

B) ra

diat

ion

Hub

ble’

s law

The

acce

lera

ting

univ

erse

and

reds

hift

(z)

The

cosm

ic sc

ale

fact

or (R

)

App

licat

ions

and

skill

s:

Des

crib

ing

both

spac

e an

d tim

e as

orig

inat

ing

with

the

Big

Bang

Des

crib

ing

the

char

acte

ristic

s of t

he C

MB

radi

atio

n

Expl

aini

ng h

ow th

e CM

B ra

diat

ion

is ev

iden

ce fo

r a H

ot B

ig B

ang

Solv

ing

prob

lem

s inv

olvi

ng z,

R a

nd H

ubbl

e’s l

aw

Estim

atin

g th

e ag

e of

the

univ

erse

by

assu

min

g a

cons

tant

exp

ansio

n ra

te

Inte

rnat

iona

l-min

dedn

ess:

Cont

ribut

ions

from

scie

ntis

ts fr

om m

any

natio

ns m

ade

the

anal

ysis

of th

e co

smic

mic

row

ave

back

grou

nd ra

diat

ion

poss

ible

Uti

lizat

ion:

Dop

pler

effe

ct (s

ee P

hysic

s sub

-top

ic 9

.5)

Aim

s: Aim

1: s

cien

tific

exp

lana

tion

of b

lack

hol

es re

quire

s a h

eigh

tene

d le

vel

of c

reat

ivity

Aim

9: o

ur li

mit

of u

nder

stan

ding

is g

uide

d by

our

abi

lity

to o

bser

ve w

ithin

ou

r uni

vers

e

Core topics

Physics guide 125

D.3

– C

osm

olog

y

Gui

danc

e:

CMB

radi

atio

n w

ill b

e co

nsid

ered

to b

e iso

tropi

c with

T≈

2.76

K

For C

MB

radi

atio

n a

simpl

e ex

plan

atio

n in

term

s of t

he u

nive

rse

cool

ing

dow

n or

di

stan

ces (

and

henc

e w

avel

engt

hs) b

eing

stre

tche

d ou

t is a

ll tha

t is r

equi

red

A qu

alita

tive

desc

riptio

n of

the

role

of t

ype

Ia su

pern

ovae

as p

rovi

ding

evi

denc

e fo

r an

acce

lera

ting

univ

erse

is re

quire

d

Dat

a bo

okle

t ref

eren

ce:

zv c

0λ λ=

∆≈

zR R

10

=−

vH

d 0=

T ≈

H1 0

Physics guide126

Esse

ntia

l ide

a: T

he la

ws o

f nuc

lear

phy

sics a

pplie

d to

nuc

lear

fusio

n pr

oces

ses i

nsid

e st

ars d

eter

min

e th

e pr

oduc

tion

of a

ll el

emen

ts u

p to

iron

.

D.4

– S

tella

r pro

cess

es

Nat

ure

of sc

ienc

e:

Obs

erva

tion

and

dedu

ctio

n: O

bser

vatio

ns o

f ste

llar s

pect

ra sh

owed

the

exis

tenc

e of

diff

eren

t ele

men

ts in

star

s. D

educ

tions

from

nuc

lear

fusio

n th

eory

wer

e ab

le to

exp

lain

th

is. (

1.8)

Und

erst

andi

ngs:

The

Jean

s crit

erio

n

Nuc

lear

fusio

n

Nuc

leos

ynth

esis

off t

he m

ain

sequ

ence

Type

Ia a

nd II

supe

rnov

ae

App

licat

ions

and

skill

s:

Appl

ying

the

Jean

s crit

erio

n to

star

form

atio

n

Des

crib

ing

the

diffe

rent

type

s of n

ucle

ar fu

sion

reac

tions

taki

ng p

lace

off

the

mai

n se

quen

ce

Appl

ying

the

mas

s–lu

min

osity

rela

tion

to co

mpa

re lif

etim

es o

n th

e m

ain

sequ

ence

rela

tive

to th

at o

f our

Sun

Des

crib

ing

the

form

atio

n of

ele

men

ts in

star

s tha

t are

hea

vier

than

iron

incl

udin

g th

e re

quire

d in

crea

ses i

n te

mpe

ratu

re

Qua

litat

ivel

y de

scrib

e th

e s a

nd r

proc

esse

s for

neu

tron

capt

ure

Dist

ingu

ishin

g be

twee

n ty

pe Ia

and

II su

pern

ovae

Aim

s: Aim

10:

ana

lysis

of n

ucle

osyn

thes

is in

volv

es th

e w

ork

of c

hem

ists

Addi

tiona

l hig

her l

evel

opt

ion

topi

cs

10 h

ours

Opt

ion

D: A

stro

phys

ics


Physics guide 127

D.4

– S

tella

r pro

cess

es

Gui

danc

e:

Onl

y an

ele

men

tary

app

licat

ion

of th

e Je

ans c

riter

ion

is re

quire

d, ie

col

laps

e of

an

inte

rste

llar c

loud

may

beg

in if

M >

Mj

Stud

ents

shou

ld b

e aw

are

of th

e us

e of

type

Ia su

pern

ovae

as s

tand

ard

cand

les


Physics guide128

Esse

ntia

l ide

a: T

he m

oder

n fie

ld o

f cos

mol

ogy

uses

adv

ance

d ex

perim

enta

l and

obs

erva

tiona

l tec

hniq

ues t

o co

llect

dat

a w

ith a

n un

prec

eden

ted

degr

ee o

f pre

cisio

n an

d as

a

resu

lt ve

ry su

rpris

ing

and

deta

iled

conc

lusio

ns a

bout

the

stru

ctur

e of

the

univ

erse

hav

e be

en re

ache

d.

D.5

– F

urth

er c

osm

olog

y

Nat

ure

of sc

ienc

e:

Cogn

itive

bia

s: Ac

cord

ing

to e

very

body

’s ex

pect

atio

ns th

e ra

te o

f exp

ansio

n of

the

univ

erse

shou

ld b

e sl

owin

g do

wn

beca

use

of g

ravi

ty. T

he d

etai

led

resu

lts fr

om th

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high

ly c

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bora

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invo

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from

all

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f kno

wle

dge:

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rimen

tal f

acts

show

that

the

expa

nsio

n of

the

univ

erse

is a

ccel

erat

ing

ye

t no

one

unde

rsta

nds w

hy. I

s thi

s an

exam

ple

of so

met

hing

that

we

will

ne

ver k

now

?

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s: Aim

2: u

nlik

e ho

w it

was

just

a fe

w d

ecad

es a

go, t

he fi

eld

of c

osm

olog

y ha

s no

w d

evel

oped

so m

uch

that

cos

mol

ogy

has b

ecom

e a

very

exa

ct sc

ienc

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th

e sa

me

leve

l as t

he re

st o

f phy

sics

Aim

10:

it is

qui

te e

xtra

ordi

nary

that

to se

ttle

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un

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se, c

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olog

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larg

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d th

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lp o

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s, th

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ysic

s of t

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ery

smal

l


Physics guide 129

D.5

– F

urth

er c

osm

olog

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Gui

danc

e:

Stud

ents

are

expe

cted

to b

e ab

le to

refe

r to

rota

tion

curv

es as

evid

ence

for d

ark

mat

ter a

nd m

ust b

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are

of ty

pes o

f can

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or d

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uden

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ith th

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and

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ator

ySt

uden

ts a

re e

xpec

ted

to d

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stra

te th

at th

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mpe

ratu

re o

f the

uni

vers

e va

ries

with

the

cosm

ic sc

ale

fact

or a

s T

R1∝

Dat

a bo

okle

t ref

eren

ce:

vG

r4

3πρ

=

H G3 8

c

2

ρπ

=

Physics guide130130

Assessment

GeneralAssessment is an integral part of teaching and learning. The most important aims of assessment in the Diploma Programme are that it should support curricular goals and encourage appropriate student learning. Both external and internal assessments are used in the Diploma Programme. IB examiners mark work produced for external assessment, while work produced for internal assessment is marked by teachers and externally moderated by the IB.

There are two types of assessment identified by the IB.

Formative assessment informs both teaching and learning. It is concerned with providing accurate and helpful feedback to students and teachers on the kind of learning taking place and the nature of students’ strengths and weaknesses in order to help develop students’ understanding and capabilities. Formative assessment can also help to improve teaching quality, as it can provide information to monitor progress towards meeting the course aims and objectives.

Summative assessment gives an overview of previous learning and is concerned with measuring student achievement.

The Diploma Programme primarily focuses on summative assessment designed to record student achievement at, or towards the end of, the course of study. However, many of the assessment instruments can also be used formatively during the course of teaching and learning, and teachers are encouraged to do this. A comprehensive assessment plan is viewed as being integral with teaching, learning and course organization. For further information, see the IB Programme standards and practices document.

The approach to assessment used by the IB is criterion-related, not norm-referenced. This approach to assessment judges students’ work by their performance in relation to identified levels of attainment, and not in relation to the work of other students. For further information on assessment within the Diploma Programme please refer to the publication Diploma Programme assessment: principles and practice.

To support teachers in the planning, delivery and assessment of the Diploma Programme courses, a variety of resources can be found on the OCC or purchased from the IB store (http://store.ibo.org). Additional publications such as specimen papers and markschemes, teacher support materials, subject reports and grade descriptors can also be found on the OCC. Past examination papers as well as markschemes can be purchased from the IB store.

Methods of assessmentThe IB uses several methods to assess work produced by students.

Assessment criteriaAssessment criteria are used when the assessment task is open-ended. Each criterion concentrates on a particular skill that students are expected to demonstrate. An assessment objective describes what students should be able to do, and assessment criteria describe how well they should be able to do it. Using assessment criteria allows discrimination between different answers and encourages a variety of responses. Each criterion comprises a set of hierarchically ordered level descriptors. Each level descriptor is worth one

Assessment in the Diploma Programme

Assessment in the Diploma Programme

Physics guide 131

or more marks. Each criterion is applied independently using a best-fit model. The maximum marks for each criterion may differ according to the criterion’s importance. The marks awarded for each criterion are added together to give the total mark for the piece of work.

MarkbandsMarkbands are a comprehensive statement of expected performance against which responses are judged. They represent a single holistic criterion divided into level descriptors. Each level descriptor corresponds to a range of marks to differentiate student performance. A best-fit approach is used to ascertain which particular mark to use from the possible range for each level descriptor.

Analytic markschemesAnalytic markschemes are prepared for those examination questions that expect a particular kind of response and/or a given final answer from students. They give detailed instructions to examiners on how to break down the total mark for each question for different parts of the response.

Marking notesFor some assessment components marked using assessment criteria, marking notes are provided. Marking notes give guidance on how to apply assessment criteria to the particular requirements of a question.

Inclusive assessment arrangementsInclusive assessment arrangements are available for candidates with assessment access requirements. These arrangements enable candidates with diverse needs to access the examinations and demonstrate their knowledge and understanding of the constructs being assessed.

The IB document Candidates with assessment access requirements provides details on all the inclusive assessment arrangements available to candidates with learning support requirements. The IB document Learning diversity within the International Baccalaureate programmes/Special educational needs within the International Baccalaureate programmes outlines the position of the IB with regard to candidates with diverse learning needs in the IB programmes. For candidates affected by adverse circumstances, the IB documents General regulations: Diploma Programme and the Handbook of procedures for the Diploma Programme provide details on special consideration.

Responsibilities of the schoolThe school is required to ensure that equal access arrangements and reasonable adjustments are provided to candidates with special educational needs that are in line with the IB documents Candidates with assessment access requirements and Learning diversity within the International Baccalaureate programmes/Special educational needs within the International Baccalaureate programmes.

Physics guide132132

Assessment

Assessment outline—SL


Component Overall weighting

(%)

Approximate weighting of

objectives (%)

Duration (hours)

1+2 3

Paper 1 20 10 10 ¾

Paper 2 40 20 20 1¼

Paper 3 20 10 10 1

Internal assessment

20Covers objectives

1, 2, 3 and 410

Physics guide 133133

Assessment outline—HL

Assessment


Component Overall weighting (%)

Approximate weighting of

objectives (%)

Duration (hours)

1+2 3

Paper 1 20 10 10 1

Paper 2 36 18 18 2¼

Paper 3 24 12 12 1¼

Internal assessment

20 Covers objectives 1, 2, 3 and 4

10

Physics guide134134

External assessment

Assessment

The method used to assess students is the use of detailed markschemes specific to each examination paper.

External assessment details—SLPaper 1 Duration: 3/4 hourWeighting: 20%Marks: 30

30 multiple-choice questions on core, about 15 of which are common with HL.

The questions on paper 1 test assessment objectives 1, 2 and 3.

The use of calculators is not permitted.

No marks are deducted for incorrect answers.

A physics data booklet is provided.

Paper 2 Duration: 1¼ hoursWeighting: 40%Marks: 50

Short-answer and extended-response questions on core material.


The use of calculators is permitted. (See calculator section on the OCC.)


Paper 3Duration: 1 hourWeighting: 20%Marks: 35

This paper will have questions on core and SL option material.

Section A: one data-based question and several short-answer questions on experimental work.

Section B: short-answer and extended-response questions from one option.




External assessment

Physics guide 135

External assessment details—HLPaper 1Duration: 1 hourWeighting: 20%Marks: 40

40 multiple-choice questions on core and AHL, about 15 of which are common with SL.


The use of calculators is not permitted.

No marks are deducted for incorrect answers.


Paper 2Duration: 2¼ hoursWeighting: 36%Marks: 95

Short-answer and extended-response questions on the core and AHL material.




Paper 3Duration: 1¼ hoursWeighting: 24%Marks: 45

This paper will have questions on core, AHL and option material.

Section A: one data-based question and several short-answer questions on experimental work.

Section B: short-answer and extended-response questions from one option.




Physics guide136136

Assessment

Internal assessment

Purpose of internal assessmentInternal assessment is an integral part of the course and is compulsory for both SL and HL students. It enables students to demonstrate the application of their skills and knowledge, and to pursue their personal interests, without the time limitations and other constraints that are associated with written examinations. The internal assessment should, as far as possible, be woven into normal classroom teaching and not be a separate activity conducted after a course has been taught.

The internal assessment requirements at SL and at HL are the same. This internal assessment section of the guide should be read in conjunction with the internal assessment section of the teacher support materials.

Guidance and authenticityThe work submitted for internal assessment must be the student’s own work. However, it is not the intention that students should decide upon a title or topic and be left to work on the internal assessment component without any further support from the teacher. The teacher should play an important role during both the planning stage and the period when the student is working on the internally assessed work. It is the responsibility of the teacher to ensure that students are familiar with:

the requirements of the type of work to be internally assessed

the IB animal experimentation policy

the assessment criteria—students must understand that the work submitted for assessment must address these criteria effectively.

Teachers and students must discuss the internally assessed work. Students should be encouraged to initiate discussions with the teacher to obtain advice and information, and students must not be penalized for seeking guidance. As part of the learning process, teachers should read and give advice to students on one draft of the work. The teacher should provide oral or written advice on how the work could be improved, but not edit the draft. The next version handed to the teacher must be the final version for submission.

It is the responsibility of teachers to ensure that all students understand the basic meaning and significance of concepts that relate to academic honesty, especially authenticity and intellectual property. Teachers must ensure that all student work for assessment is prepared according to the requirements and must explain clearly to students that the internally assessed work must be entirely their own. Where collaboration between students is permitted, it must be clear to all students what the difference is between collaboration and collusion.

All work submitted to the IB for moderation or assessment must be authenticated by a teacher, and must not include any known instances of suspected or confirmed academic misconduct. Each student must confirm that the work is his or her authentic work and constitutes the final version of that work. Once a student has officially submitted the final version of the work it cannot be retracted. The requirement to confirm the authenticity of work applies to the work of all students, not just the sample work that will be submitted to the IB for the purpose of moderation. For further details refer to the IB publications Academic honesty (2011), The Diploma Programme: From principles into practice (2009) and the relevant articles in General regulations: Diploma Programme (2012).

Internal assessment

Physics guide 137

Authenticity may be checked by discussion with the student on the content of the work, and scrutiny of one or more of the following:

the student’s initial proposal

the first draft of the written work

the references cited

the style of writing compared with work known to be that of the student

the analysis of the work by a web-based plagiarism detection service such as http://www.turnitin.com.

The same piece of work cannot be submitted to meet the requirements of both the internal assessment and the extended essay.

Group workEach investigation is an individual piece of work based on different data collected or measurements generated. Ideally, students should work on their own when collecting data. In some cases, data collected or measurements made can be from a group experiment provided each student collected his or her own data or made his or her own measurements. In physics, in some cases, group data or measurements may be combined to provide enough for individual analysis. Even in this case, students should have collected and recorded their own data and they should clearly indicate which data are theirs.

It should be made clear to students that all work connected with the investigation should be their own. It is therefore helpful if teachers try to encourage in students a sense of responsibility for their own learning so that they accept a degree of ownership and take pride in their own work.

Time allocationInternal assessment is an integral part of the physics course, contributing 20% to the final assessment in the SL and the HL courses. This weighting should be reflected in the time that is allocated to teaching the knowledge, skills and understanding required to undertake the work, as well as the total time allocated to carry out the work.

It is recommended that a total of approximately 10 hours of teaching time for both SL and HL should be allocated to the work. This should include:

time for the teacher to explain to students the requirements of the internal assessment

class time for students to work on the internal assessment component and ask questions

time for consultation between the teacher and each student

time to review and monitor progress, and to check authenticity.

Safety requirements and recommendationsWhile teachers are responsible for following national or local guidelines, which may differ from country to country, attention should be given to the guidelines below, which were developed for the International Council of Associations for Science Education (ICASE) Safety Committee by The Laboratory Safety Institute (LSI).

It is a basic responsibility of everyone involved to make safety and health an ongoing commitment. Any advice given will acknowledge the need to respect the local context, the varying educational and cultural traditions, the financial constraints and the legal systems of differing countries.

Internal assessment

Physics guide138

The Laboratory Safety Institute’s Laboratory Safety Guidelines...40 suggestions for a safer labSteps Requiring Minimal Expense

1. Have a written health, safety and environmental affairs (HS&E) policy statement.

2. Organize a departmental HS&E committee of employees, management, faculty, staff and students that will meet regularly to discuss HS&E issues.

3. Develop an HS&E orientation for all new employees and students.

4. Encourage employees and students to care about their health and safety and that of others.

5. Involve every employee and student in some aspect of the safety program and give each specific responsibilities.

6. Provide incentives to employees and students for safety performance.

7. Require all employees to read the appropriate safety manual. Require students to read the institution’s laboratory safety rules. Have both groups sign a statement that they have done so, understand the contents, and agree to follow the procedures and practices. Keep these statements on file in the department office

8. Conduct periodic, unannounced laboratory inspections to identify and correct hazardous conditions and unsafe practices. Involve students and employees in simulated OSHA inspections.

9. Make learning how to be safe an integral and important part of science education, your work, and your life.

10. Schedule regular departmental safety meetings for all students and employees to discuss the results of inspections and aspects of laboratory safety.

11. When conducting experiments with hazards or potential hazards, ask yourself these questions:

– What are the hazards?

– What are the worst possible things that could go wrong?

– How will I deal with them?

– What are the prudent practices, protective facilities and equipment necessary to minimize the risk of exposure to the hazards?

12. Require that all accidents (incidents) be reported, evaluated by the departmental safety committee, and discussed at departmental safety meetings.

13. Require every pre-lab/pre-experiment discussion to include consideration of the health and safety aspects.

14. Don’t allow experiments to run unattended unless they are failsafe.

15. Forbid working alone in any laboratory and working without prior knowledge of a staff member.

16. Extend the safety program beyond the laboratory to the automobile and the home.

17. Allow only minimum amounts of flammable liquids in each laboratory.

18. Forbid smoking, eating and drinking in the laboratory.

19. Do not allow food to be stored in chemical refrigerators.

20. Develop plans and conduct drills for dealing with emergencies such as fire, explosion, poisoning, chemical spill or vapour release, electric shock, bleeding and personal contamination.

21. Require good housekeeping practices in all work areas.

Internal assessment

Physics guide 139

22. Display the phone numbers of the fire department, police department, and local ambulance either on or immediately next to every phone.

23. Store acids and bases separately. Store fuels and oxidizers separately.

24. Maintain a chemical inventory to avoid purchasing unnecessary quantities of chemicals.

25. Use warning signs to designate particular hazards.

26. Develop specific work practices for individual experiments, such as those that should be conducted only in a ventilated hood or involve particularly hazardous materials. When possible most hazardous experiments should be done in a hood.

Steps Requiring Moderate Expense

27. Allocate a portion of the departmental budget to safety.

28. Require the use of appropriate eye protection at all times in laboratories and areas where chemicals are transported.

29. Provide adequate supplies of personal protective equipment—safety glasses, goggles, face shields, gloves, lab coats and bench top shields.

30. Provide fire extinguishers, safety showers, eye wash fountains, first aid kits, fire blankets and fume hoods in each laboratory and test or check monthly.

31. Provide guards on all vacuum pumps and secure all compressed gas cylinders.

32. Provide an appropriate supply of first aid equipment and instruction on its proper use.

33. Provide fireproof cabinets for storage of flammable chemicals.

34. Maintain a centrally located departmental safety library:

– “Safety in School Science Labs”, Clair Wood, 1994, Kaufman & Associates, 101 Oak Street, Wellesley, MA 02482

– “The Laboratory Safety Pocket Guide”, 1996, Genium Publisher, One Genium Plaza, Schnectady, NY

– “Safety in Academic Chemistry Laboratories”, ACS, 1155 Sixteenth Street NW, Washington, DC 20036

– “Manual of Safety and Health Hazards in The School Science Laboratory”, “Safety in the School Science Laboratory”, “School Science Laboratories: A guide to Some Hazardous Substances” Council of State Science Supervisors (now available only from LSI.)

– “Handbook of Laboratory Safety”, 4th Edition, CRC Press, 2000 Corporate Boulevard NW, Boca Raton, FL 33431

– “Fire Protection Guide on Hazardous Materials”, National Fire Protection Association, Batterymarch Park, Quincy, MA 02269

– ”Prudent Practices in the Laboratory: Handling and Disposal of Hazardous Chemicals”, 2nd Edition, 1995

– “Biosafety in the Laboratory”, National Academy Press, 2101 Constitution Avenue, NW, Washington, DC 20418

– “Learning By Accident”, Volumes 1–3, 1997–2000, The Laboratory Safety Institute, Natick, MA 01760

(All are available from LSI.)

35. Remove all electrical connections from inside chemical refrigerators and require magnetic closures.

Internal assessment

Physics guide140

36. Require grounded plugs on all electrical equipment and install ground fault interrupters (GFIs) where appropriate.

37. Label all chemicals to show the name of the material, the nature and degree of hazard, the appropriate precautions, and the name of the person responsible for the container.

38. Develop a program for dating stored chemicals and for recertifying or discarding them after predetermined maximum periods of storage.

39. Develop a system for the legal, safe and ecologically acceptable disposal of chemical wastes.

40. Provide secure, adequately spaced, well-ventilated storage of chemicals.

Internal assessment

Physics guide 141

Using assessment criteria for internal assessmentFor internal assessment, a number of assessment criteria have been identified. Each assessment criterion has level descriptors describing specific achievement levels, together with an appropriate range of marks. The level descriptors concentrate on positive achievement, although for the lower levels failure to achieve may be included in the description.

Teachers must judge the internally assessed work at SL and at HL against the criteria using the level descriptors.

Assessment criteria are the same for both SL and HL.

The aim is to find, for each criterion, the descriptor that conveys most accurately the level attained by the student, using the best-fit model. A best-fit approach means that compensation should be made when a piece of work matches different aspects of a criterion at different levels. The mark awarded should be one that most fairly reflects the balance of achievement against the criterion. It is not necessary for every single aspect of a level descriptor to be met for that mark to be awarded.

When assessing a student’s work, teachers should read the level descriptors for each criterion until they reach a descriptor that most appropriately describes the level of the work being assessed. If a piece of work seems to fall between two descriptors, both descriptors should be read again and the one that more appropriately describes the student’s work should be chosen.

Where there are two or more marks available within a level, teachers should award the upper marks if the student’s work demonstrates the qualities described to a great extent; the work may be close to achieving marks in the level above. Teachers should award the lower marks if the student’s work demonstrates the qualities described to a lesser extent; the work may be close to achieving marks in the level below.

Only whole numbers should be recorded; partial marks (fractions and decimals) are not acceptable.

Teachers should not think in terms of a pass or fail boundary, but should concentrate on identifying the appropriate descriptor for each assessment criterion.

The highest level descriptors do not imply faultless performance but should be achievable by a student. Teachers should not hesitate to use the extremes if they are appropriate descriptions of the work being assessed.

A student who attains a high achievement level in relation to one criterion will not necessarily attain high achievement levels in relation to the other criteria. Similarly, a student who attains a low achievement level for one criterion will not necessarily attain low achievement levels for the other criteria. Teachers should not assume that the overall assessment of the students will produce any particular distribution of marks.

It is recommended that the assessment criteria be made available to students.

Internal assessment

Physics guide142

Practical work and internal assessmentGeneral introductionThe internal assessment requirements are the same for biology, chemistry and physics. The internal assessment, worth 20% of the final assessment, consists of one scientific investigation. The individual investigation should cover a topic that is commensurate with the level of the course of study.

Student work is internally assessed by the teacher and externally moderated by the IB. The performance in internal assessment at both SL and HL is marked against common assessment criteria, with a total mark out of 24.

Note: Any investigation that is to be used to assess students should be specifically designed to match the relevant assessment criteria.

The internal assessment task will be one scientific investigation taking about 10 hours and the write-up should be about 6 to 12 pages long. Investigations exceeding this length will be penalized in the communications criterion as lacking in conciseness.

The practical investigation, with generic criteria, will allow a wide range of practical activities satisfying the varying needs of biology, chemistry and physics. The investigation addresses many of the learner profile attributes well. See section on “Approaches to the teaching and learning of physics” for further links.

The task produced should be complex and commensurate with the level of the course. It should require a purposeful research question and the scientific rationale for it. The marked exemplar material in the teacher support materials will demonstrate that the assessment will be rigorous and of the same standard as the assessment in the previous courses.

Some of the possible tasks include:

a hands-on laboratory investigation

using a spreadsheet for analysis and modelling

extracting data from a database and analysing it graphically

producing a hybrid of spreadsheet/database work with a traditional hands-on investigation

using a simulation, provided it is interactive and open-ended

Some task may consist of relevant and appropriate qualitative work combined with quantitative work.

The tasks include the traditional hands-on practical investigations as in the previous course. The depth of treatment required for hands-on practical investigations is unchanged from the previous internal assessment and will be shown in detail in the teacher support materials. In addition, detailed assessment of specific aspects of hands-on practical work will be assessed in the written papers as detailed in the relevant topic(s) in the “Syllabus content” section of the guide.

The task will have the same assessment criteria for SL and HL. The five assessment criteria are personalengagement, exploration, analysis, evaluation and communication.

Internal assessment

Physics guide 143

Internal assessment detailsInternal assessment componentDuration: 10 hoursWeighting: 20%

Individual investigation

This investigation covers assessment objectives 1, 2, 3 and 4.

Internal assessment criteriaThe new assessment model uses five criteria to assess the final report of the individual investigation with the following raw marks and weightings assigned:

Personal engagement

Exploration Analysis Evaluation Communication Total

2 (8%) 6 (25%) 6 (25%) 6 (25%) 4 (17%) 24 (100%)

Levels of performance are described using multiple indicators per level. In many cases the indicators occur together in a specific level, but not always. Also, not all indicators are always present. This means that a candidate can demonstrate performances that fit into different levels. To accommodate this, the IB assessment models use markbands and advise examiners and teachers to use a best-fit approach in deciding the appropriate mark for a particular criterion.

Teachers should read the guidance on using markbands shown above in the section called “Using assessment criteria for internal assessment” before starting to mark. It is also essential to be fully acquainted with the marking of the exemplars in the teacher support material. The precise meaning of the command terms used in the criteria can be found in the glossary of the subject guides.

Personal engagement

This criterion assesses the extent to which the student engages with the exploration and makes it their own. Personal engagement may be recognized in different attributes and skills. These could include addressing personal interests or showing evidence of independent thinking, creativity or initiative in the designing, implementation or presentation of the investigation.

Mark Descriptor

0 The student’s report does not reach a standard described by the descriptors below.

1 The evidence of personal engagement with the exploration is limited with little independent thinking, initiative or creativity.

The justification given for choosing the research question and/or the topic under investigation does not demonstrate personal significance, interest or curiosity.

There is little evidence of personal input and initiative in the designing, implementation or presentation of the investigation.

Internal assessment

Physics guide144

2 The evidence of personal engagement with the exploration is clear with significant independent thinking, initiative or creativity.

The justification given for choosing the research question and/or the topic under investigation demonstrates personal significance, interest or curiosity.

There is evidence of personal input and initiative in the designing, implementation or presentation of the investigation.

Exploration

This criterion assesses the extent to which the student establishes the scientific context for the work, states a clear and focused research question and uses concepts and techniques appropriate to the Diploma Programme level. Where appropriate, this criterion also assesses awareness of safety, environmental, and ethical considerations.

Mark Descriptor


1–2 The topic of the investigation is identified and a research question of some relevance is stated but it is not focused.

The background information provided for the investigation is superficial or of limited relevance and does not aid the understanding of the context of the investigation.

The methodology of the investigation is only appropriate to address the research question to a very limited extent since it takes into consideration few of the significant factors that may influence the relevance, reliability and sufficiency of the collected data.

The report shows evidence of limited awareness of the significant safety, ethical or environmental issues that are relevant to the methodology of the investigation*.

3–4 The topic of the investigation is identified and a relevant but not fully focused research question is described.

The background information provided for the investigation is mainly appropriate and relevant and aids the understanding of the context of the investigation.

The methodology of the investigation is mainly appropriate to address the research question but has limitations since it takes into consideration only some of the significant factors that may influence the relevance, reliability and sufficiency of the collected data.

The report shows evidence of some awareness of the significant safety, ethical or environmental issues that are relevant to the methodology of the investigation*.

5–6 The topic of the investigation is identified and a relevant and fully focused research question is clearly described.

The background information provided for the investigation is entirely appropriate and relevant and enhances the understanding of the context of the investigation.

The methodology of the investigation is highly appropriate to address the research question because it takes into consideration all, or nearly all, of the significant factors that may influence the relevance, reliability and sufficiency of the collected data.

The report shows evidence of full awareness of the significant safety, ethical or environmental issues that are relevant to the methodology of the investigation.*

* This indicator should only be applied when appropriate to the investigation. See exemplars in teacher support material.

Internal assessment

Physics guide 145

AnalysisThis criterion assesses the extent to which the student’s report provides evidence that the student has selected, recorded, processed and interpreted the data in ways that are relevant to the research question and can support a conclusion.

Mark Descriptor


1–2 The report includes insufficient relevant raw data to support a valid conclusion to the research question.

Some basic data processing is carried out but is either too inaccurate or too insufficient to lead to a valid conclusion.

The report shows evidence of little consideration of the impact of measurement uncertainty on the analysis.

The processed data is incorrectly or insufficiently interpreted so that the conclusion is invalid or very incomplete.

3–4 The report includes relevant but incomplete quantitative and qualitative raw data that could support a simple or partially valid conclusion to the research question.

Appropriate and sufficient data processing is carried out that could lead to a broadly valid conclusion but there are significant inaccuracies and inconsistencies in the processing.

The report shows evidence of some consideration of the impact of measurement uncertainty on the analysis.

The processed data is interpreted so that a broadly valid but incomplete or limited conclusion to the research question can be deduced.

5–6 The report includes sufficient relevant quantitative and qualitative raw data that could support a detailed and valid conclusion to the research question.

Appropriate and sufficient data processing is carried out with the accuracy required to enable a conclusion to the research question to be drawn that is fully consistent with the experimental data.

The report shows evidence of full and appropriate consideration of the impact of measurement uncertainty on the analysis.

The processed data is correctly interpreted so that a completely valid and detailed conclusion to the research question can be deduced.

Internal assessment

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EvaluationThis criterion assesses the extent to which the student’s report provides evidence of evaluation of the investigation and the results with regard to the research question and the accepted scientific context.

Mark Descriptor


1–2 A conclusion is outlined which is not relevant to the research question or is not supported by the data presented.

The conclusion makes superficial comparison to the accepted scientific context.

Strengths and weaknesses of the investigation, such as limitations of the data and sources of error, are outlined but are restricted to an account of the practical or procedural issues faced.

The student has outlined very few realistic and relevant suggestions for the improvement and extension of the investigation.

3–4 A conclusion is described which is relevant to the research question and supported by the data presented.

A conclusion is described which makes some relevant comparison to the accepted scientific context.

Strengths and weaknesses of the investigation, such as limitations of the data and sources of error, are described and provide evidence of some awareness of the methodological issues* involved in establishing the conclusion.

The student has described some realistic and relevant suggestions for the improvement and extension of the investigation.

5–6 A detailed conclusion is described and justified which is entirely relevant to the research question and fully supported by the data presented.

A conclusion is correctly described and justified through relevant comparison to the accepted scientific context.

Strengths and weaknesses of the investigation, such as limitations of the data and sources of error, are discussed and provide evidence of a clear understanding of the methodological issues* involved in establishing the conclusion.

The student has discussed realistic and relevant suggestions for the improvement and extension of the investigation.

*See exemplars in teacher support material for clarification.

Internal assessment

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CommunicationThis criterion assesses whether the investigation is presented and reported in a way that supports effective communication of the focus, process and outcomes.

Mark Descriptor


1–2 The presentation of the investigation is unclear, making it difficult to understand the focus, process and outcomes.

The report is not well structured and is unclear: the necessary information on focus, process and outcomes is missing or is presented in an incoherent or disorganized way.

The understanding of the focus, process and outcomes of the investigation is obscured by the presence of inappropriate or irrelevant information.

There are many errors in the use of subject specific terminology and conventions*.

3–4 The presentation of the investigation is clear. Any errors do not hamper understanding of the focus, process and outcomes.

The report is well structured and clear: the necessary information on focus, process and outcomes is present and presented in a coherent way.

The report is relevant and concise thereby facilitating a ready understanding of the focus, process and outcomes of the investigation.

The use of subject-specific terminology and conventions is appropriate and correct. Any errors do not hamper understanding.

*For example, incorrect/missing labelling of graphs, tables, images; use of units, decimal places. For issues of referencing and citations refer to the “Academic honesty” section.

Rationale for practical workAlthough the requirements for IA are centred on the investigation, the different types of practical activities that a student may engage in serve other purposes, including:

illustrating, teaching and reinforcing theoretical concepts

developing an appreciation of the essential hands-on nature of much scientific work

developing an appreciation of scientists’ use of secondary data from databases

developing an appreciation of scientists’ use of modelling

developing an appreciation of the benefits and limitations of scientific methodology.

Practical scheme of workThe practical scheme of work (PSOW) is the practical course planned by the teacher and acts as a summary of all the investigative activities carried out by a student. Students at SL and HL in the same subject may carry out some of the same investigations.

Internal assessment

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Syllabus coverageThe range of practical work carried out should reflect the breadth and depth of the subject syllabus at each level, but it is not necessary to carry out an investigation for every syllabus topic. However, all students must participate in the group 4 project and the IA investigation.

Planning your practical scheme of workTeachers are free to formulate their own practical schemes of work by choosing practical activities according to the requirements outlined. Their choices should be based on:

subjects, levels and options taught

the needs of their students

available resources

teaching styles.

Each scheme must include some complex experiments that make greater conceptual demands on students. A scheme made up entirely of simple experiments, such as ticking boxes or exercises involving filling in tables, will not provide an adequate range of experience for students.

Teachers are encouraged to use the online curriculum centre (OCC) to share ideas about possible practical activities by joining in the discussion forums and adding resources in the subject home pages.

FlexibilityThe practical programme is flexible enough to allow a wide variety of practical activities to be carried out. These could include:

short labs or projects extending over several weeks

computer simulations

using databases for secondary data

developing and using models

data-gathering exercises such as questionnaires, user trials and surveys

data-analysis exercises

fieldwork.

Practical work documentationDetails of the practical scheme of work are recorded on Form 4/PSOW provided in the Handbook of procedures for the Diploma Programme. A copy of the class 4/PSOW form must be included with any sample set sent for moderation.

Time allocation for practical workThe recommended teaching times for all Diploma Programme courses are 150 hours at SL and 240 hours at HL. Students at SL are required to spend 40 hours, and students at HL 60 hours, on practical activities (excluding time spent writing up work). These times include 10 hours for the group 4 project and 10 hours for the internal assessment investigation. (Only 2–3 hours of investigative work can be carried out after the deadline for submitting work to the moderator and still be counted in the total number of hours for the practical scheme of work.)


Assessment

The group 4 project

The group 4 project is an interdisciplinary activity in which all Diploma Programme science students must participate. The intention is that students from the different group 4 subjects analyse a common topic or problem. The exercise should be a collaborative experience where the emphasis is on the processes involved in, rather than the products of, such an activity.

In most cases students in a school would be involved in the investigation of the same topic. Where there are large numbers of students, it is possible to divide them into several smaller groups containing representatives from each of the science subjects. Each group may investigate the same topic or different topics—that is, there may be several group 4 projects in the same school.

Students studying environmental systems and societies are not required to undertake the group 4 project.

Summary of the group 4 projectThe group 4 project is a collaborative activity where students from different group 4 subjects work together on a scientific or technological topic, allowing for concepts and perceptions from across the disciplines to be shared in line with aim 10—that is, to “develop an understanding of the relationships between scientific disciplines and their influence on other areas of knowledge”. The project can be practically or theoretically based. Collaboration between schools in different regions is encouraged.

The group 4 project allows students to appreciate the environmental, social and ethical implications of science and technology. It may also allow them to understand the limitations of scientific study, for example, the shortage of appropriate data and/or the lack of resources. The emphasis is on interdisciplinary cooperation and the processes involved in scientific investigation, rather than the products of such investigation.

The choice of scientific or technological topic is open but the project should clearly address aims 7, 8 and 10 of the group 4 subject guides.

Ideally, the project should involve students collaborating with those from other group 4 subjects at all stages. To this end, it is not necessary for the topic chosen to have clearly identifiable separate subject components. However, for logistical reasons, some schools may prefer a separate subject “action” phase (see the following “Project stages” section).

Project stagesThe 10 hours allocated to the group 4 project, which are part of the teaching time set aside for developing the practical scheme of work, can be divided into three stages: planning, action and evaluation.

PlanningThis stage is crucial to the whole exercise and should last about two hours.

The planning stage could consist of a single session, or two or three shorter ones.

This stage must involve all group 4 students meeting to “brainstorm” and discuss the central topic, sharing ideas and information.

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The topic can be chosen by the students themselves or selected by the teachers.

Where large numbers of students are involved, it may be advisable to have more than one mixed subject group.

After selecting a topic or issue, the activities to be carried out must be clearly defined before moving from the planning stage to the action and evaluation stages.

A possible strategy is that students define specific tasks for themselves, either individually or as members of groups, and investigate various aspects of the chosen topic. At this stage, if the project is to be experimentally based, apparatus should be specified so that there is no delay in carrying out the action stage. Contact with other schools, if a joint venture has been agreed, is an important consideration at this time.

ActionThis stage should last around six hours and may be carried out over one or two weeks in normal scheduled class time. Alternatively, a whole day could be set aside if, for example, the project involves fieldwork.

Students should investigate the topic in mixed-subject groups or single-subject groups.

There should be collaboration during the action stage; findings of investigations should be shared with other students within the mixed/single-subject group. During this stage, in any practically-based activity, it is important to pay attention to safety, ethical and environmental considerations.

Note: Students studying two group 4 subjects are not required to do two separate action phases.

EvaluationThe emphasis during this stage, for which two hours are probably necessary, is on students sharing their findings, both successes and failures, with other students. How this is achieved can be decided by the teachers, the students or jointly.

One solution is to devote a morning, afternoon or evening to a symposium where all the students, as individuals or as groups, give brief presentations.

Alternatively, the presentation could be more informal and take the form of a science fair where students circulate around displays summarizing the activities of each group.

The symposium or science fair could also be attended by parents, members of the school board and the press. This would be especially pertinent if some issue of local importance has been researched. Some of the findings might influence the way the school interacts with its environment or local community.

Addressing aims 7 and 8Aim 7: “develop and apply 21st century communication skills in the study of science.”

Aim 7 may be partly addressed at the planning stage by using electronic communication within and between schools. It may be that technology (for example, data logging, spreadsheets, databases and so on) will be used in the action phase and certainly in the presentation/evaluation stage (for example, use of digital images, presentation software, websites, digital video and so on).

Aim 8: “become critically aware, as global citizens, of the ethical implications of using science and technology.”

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Addressing the international dimensionThere are also possibilities in the choice of topic to illustrate the international nature of the scientific endeavour and the increasing cooperation required to tackle global issues involving science and technology. An alternative way to bring an international dimension to the project is to collaborate with a school in another region.

Types of projectWhile addressing aims 7, 8 and 10 the project must be based on science or its applications. The project may have a hands-on practical action phase or one involving purely theoretical aspects. It could be undertaken in a wide range of ways:

designing and carrying out a laboratory investigation or fieldwork

carrying out a comparative study (experimental or otherwise) in collaboration with another school

collating, manipulating and analysing data from other sources, such as scientif ic journals, environmental organizations, science and technology industries and government reports

designing and using a model or simulation

contributing to a long-term project organized by the school.

Logistical strategiesThe logistical organization of the group 4 project is often a challenge to schools. The following models illustrate possible ways in which the project may be implemented.

Models A, B and C apply within a single school, and model D relates to a project involving collaboration between schools.

Model A: mixed-subject groups and one topic

Schools may adopt mixed subject groups and choose one common topic. The number of groups will depend on the number of students.

Model B: mixed-subject groups adopting more than one topic

Schools with large numbers of students may choose to do more than one topic.

Model C: single-subject groups

For logistical reasons some schools may opt for single subject groups, with one or more topics in the action phase. This model is less desirable as it does not show the mixed subject collaboration in which many scientists are involved.

Model D: collaboration with another school

The collaborative model is open to any school. To this end, the IB provides an electronic collaboration board on the OCC where schools can post their project ideas and invite collaboration from other schools. This could range from merely sharing evaluations for a common topic to a full-scale collaborative venture at all stages.

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For schools with few Diploma Programme (course) students it is possible to work with non-Diploma Programme or non-group 4 students or undertake the project once every two years. However, these schools are encouraged to collaborate with another school. This strategy is also recommended for individual students who may not have participated in the project, for example, through illness or because they have transferred to a new school where the project has already taken place.

TimingThe 10 hours that the IB recommends be allocated to the project may be spread over a number of weeks. The distribution of these hours needs to be taken into account when selecting the optimum time to carry out the project. However, it is possible for a group to dedicate a period of time exclusively to project work if all/most other schoolwork is suspended.

Year 1In the first year, students’ experience and skills may be limited and it would be inadvisable to start the project too soon in the course. However, doing the project in the final part of the first year may have the advantage of reducing pressure on students later on. This strategy provides time for solving unexpected problems.

Year 1–year 2The planning stage could start, the topic could be decided upon, and provisional discussion in individual subjects could take place at the end of the first year. Students could then use the vacation time to think about how they are going to tackle the project and would be ready to start work early in the second year.

Year 2Delaying the start of the project until some point in the second year, particularly if left too late, increases pressure on students in many ways: the schedule for finishing the work is much tighter than for the other options; the illness of any student or unexpected problems will present extra difficulties. Nevertheless, this choice does mean students know one another and their teachers by this time, have probably become accustomed to working in a team and will be more experienced in the relevant fields than in the first year.

Combined SL and HL

Where circumstances dictate that the project is only carried out every two years, HL beginners and more experienced SL students can be combined.

Selecting a topicStudents may choose the topic or propose possible topics and the teacher then decides which one is the most viable based on resources, staff availability and so on. Alternatively, the teacher selects the topic or proposes several topics from which students make a choice.

Student selection

Students are likely to display more enthusiasm and feel a greater sense of ownership for a topic that they have chosen themselves. A possible strategy for student selection of a topic, which also includes part of the planning stage, is outlined here. At this point, subject teachers may provide advice on the viability of proposed topics.

Identify possible topics by using a questionnaire or a survey of students.

Conduct an initial “brainstorming” session of potential topics or issues.

Discuss, briefly, two or three topics that seem interesting.

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Select one topic by consensus.

Students make a list of potential investigations that could be carried out. All students then discuss issues such as possible overlap and collaborative investigations.

A reflective statement written by each student on their involvement in the group 4 project must be included on the cover sheet for each internal assessment investigation. See Handbook of procedures for the Diploma Programme for more details.

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Glossary of command terms

Appendices

Command terms for physicsStudents should be familiar with the following key terms and phrases used in examination questions, which are to be understood as described below. Although these terms will be used frequently in examination questions, other terms may be used to direct students to present an argument in a specific way.

These command terms indicate the depth of treatment required.

Assessment objective 1

Command term Definition

Define Give the precise meaning of a word, phrase, concept or physical quantity.

Draw Represent by means of a labelled, accurate diagram or graph, using a pencil. A ruler (straight edge) should be used for straight lines. Diagrams should be drawn to scale. Graphs should have points correctly plotted (if appropriate) and joined in a straight line or smooth curve.

Label Add labels to a diagram.

List Give a sequence of brief answers with no explanation.

Measure Obtain a value for a quantity.

State Give a specific name, value or other brief answer without explanation or calculation.

Write down Obtain the answer(s), usually by extracting information. Little or no calculation is required. Working does not need to be shown.



Annotate Add brief notes to a diagram or graph.

Apply Use an idea, equation, principle, theory or law in relation to a given problem or issue.

Calculate Obtain a numerical answer showing the relevant stages in the working.

Describe Give a detailed account.

Distinguish Make clear the differences between two or more concepts or items.

Estimate Obtain an approximate value.

Formulate Express precisely and systematically the relevant concept(s) or argument(s).


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Identify Provide an answer from a number of possibilities.

Outline Give a brief account or summary.

Plot Mark the position of points on a diagram.



Analyse Break down in order to bring out the essential elements or structure.

Comment Give a judgment based on a given statement or result of a calculation.

Compare Give an account of the similarities between two (or more) items or situations, referring to both (all) of them throughout.

Compareand contrast

Give an account of similarities and differences between two (or more) items or situations, referring to both (all) of them throughout.

Construct Display information in a diagrammatic or logical form.

Deduce Reach a conclusion from the information given.

Demonstrate Make clear by reasoning or evidence, illustrating with examples or practical application.

Derive Manipulate a mathematical relationship to give a new equation or relationship.

Design Produce a plan, simulation or model.

Determine Obtain the only possible answer.

Discuss Offer a considered and balanced review that includes a range of arguments, factors or hypotheses. Opinions or conclusions should be presented clearly and supported by appropriate evidence.

Evaluate Make an appraisal by weighing up the strengths and limitations.

Explain Give a detailed account including reasons or causes.

Hence Use the preceding work to obtain the required result.

Hence or otherwise It is suggested that the preceding work is used, but other methods could also receive credit.

Justify Give valid reasons or evidence to support an answer or conclusion.

Predict Give an expected result.

Show Give the steps in a calculation or derivation.

Show that Obtain the required result (possibly using information given) without the formality of proof. “Show that” questions do not generally require the use of a calculator.


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Sketch Represent by means of a diagram or graph (labelled as appropriate). The sketch should give a general idea of the required shape or relationship, and should include relevant features.

Solve Obtain the answer(s) using algebraic and/or numerical and/or graphical methods.

Suggest Propose a solution, hypothesis or other possible answer.


Appendices

Bibliography

This bibliography lists the principal works used to inform the curriculum review. It is not an exhaustive list and does not include all the literature available: judicious selection was made in order to better advise and guide teachers. This bibliography is not a list of recommended textbooks.

Rhoton, J. 2010. Science Education Leadership: Best Practices for the New Century. Arlington, Virginia, USA. National Science Teachers Association Press.

Masood, E. 2009. Science & Islam: A History. London, UK. Icon Books.

Roberts, B. 2009. Educating for Global Citizenship: A Practical Guide for Schools. Cardiff, UK. International Baccalaureate Organization.

Martin, J. 2006. The Meaning of the 21st Century: A vital blueprint for ensuring our future. London, UK. Eden Project Books.

Gerzon, M. 2010. Global Citizens: How our vision of the world is outdated, and what we can do about it. London, UK. Rider Books.

Haydon, G. 2006. Education, Philosophy & the Ethical Environment. Oxon/New York, USA. Routledge.

Anderson, LW et al. 2001. A Taxonomy for Learning, Teaching, and Assessing: A Revision of Bloom’s Taxonomy of Educational Objectives. New York, USA. Addison Wesley Longman, Inc.

Hattie, J. 2009. Visible learning: A synthesis of over 800 meta-analyses relating to achievement. Oxon/New York, USA. Routledge.

Petty, G. 2009. Evidence-based Teaching: A practical approach. (2nd edition). Cheltenham, UK. Nelson Thornes Ltd.

Andain, I and Murphy, G. 2008. Creating Lifelong Learners: Challenges for Education in the 21st Century. Cardiff, UK. International Baccalaureate Organization.

Jewkes, J, Sawers, D and Stillerman, R. 1969. The Sources of Invention. (2nd edition). New York, USA. W.W. Norton & Co.

Lawson, B. 2005. How Designers Think: The design process demystified. (4th edition). Oxford, UK. Architectural Press.

Douglas, H. 2009. Science, Policy, and the Value-Free Ideal. Pittsburgh, Pennsylvania, USA. University of Pittsburgh Press.

Aikenhead, G and Michell, H. 2011. Bridging Cultures: Indigenous and Scientific Ways of Knowing Nature. Toronto, Canada. Pearson Canada.

Winston, M and Edelbach, R. 2012. Society, Ethics, and Technology. (4th edition). Boston, Massachusetts, USA. Wadsworth CENGAGE Learning.

Brian Arthur, W. 2009. The Nature of Technology. London, UK. Penguin Books.

Headrick, D. 2009. Technology: A World History. Oxford, UK. Oxford University Press.

Bibliography

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Popper, KR. 1980. The Logic of Scientific Discovery. (4th revised edition). London, UK. Hutchinson.

Trefil, J. 2008. Why Science?. New York/Arlington, USA. NSTA Press & Teachers College Press.

Kuhn, TS. 1996. The Structure of Scientific Revolutions. (3rd edition). Chicago, Illinois, USA. The University of Chicago Press.

Khine, MS, (ed.). 2012. Advances in Nature of Science Research: Concepts and Methodologies. Bahrain. Springer.

Spier, F. 2010. Big History and the Future of Humanity. Chichester, UK. Wiley-Blackwell.

Stokes Brown, C. 2007. Big History: From the Big Bang to the Present. New York, USA. The New Press.

Swain, H, (ed.). 2002. Big Questions in Sciences. London, UK. Vintage.

Roberts, RM. 1989. Serendipity: Accidental Discoveries in Science. Chichester, UK. Wiley Science Editions.

Ehrlich, R. 2001. Nine crazy ideas in science. Princeton, New Jersey, USA. Princeton University Press.

Lloyd, C. 2012. What on Earth Happened?: The Complete Story of the Planet, Life and People from the Big Bang to the Present Day. London, UK. Bloomsbury Publishing.

Trefil, J and Hazen, RM. 2010. Sciences: An integrated Approach. (6th edition). Chichester, UK. Wiley.

ICASE. 2010. Innovation in Science & Technology Education: Research, Policy, Practice. Tartu, Estonia. ICASE/UNESCO/University of Tartu.

American Association for the Advancement of Science. 1990. Science for all Americans online. Washington, USA. http://www.project2061.org/publications/sfaa/online/sfaatoc.htm.

The Geological Society of America. 2012. Nature of Science and the Scientific Method. Boulder, Colorado, USA. http://www.geosociety.org/educate/naturescience.pdf.

Big History Project. 2011. Big History: An Introduction to Everything. http://www.bighistoryproject.com.

Nuffield Foundation. 2012. How science works. London, UK. http://www.nuffieldfoundation.org/practical-physics/how-science-works

Understanding Science. 1 February 2013. http://www.understandingscience.org.

Collins, S, Osborne, J, Ratcliffe, M, Millar, R, and Duschl, R. 2012. What ‘ideas-about-science’ should be taught in school science? A Delphi study of the ‘expert’ community. St Louis, Missouri, USA. National Association for Research in Science Teaching (NARST).

TIMSS (The Trends in International Mathematics and Science Study). 1 February 2013. http://timssandpirls.bc.edu.

PISA (Programme for International Student Assessment). 1 February 2013. http://www.oecd.org/pisa.

ROSE (The Relevance of Science Education). 1 February 2013. http://roseproject.no/.

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