Chapter 1 Science&Technology. Science: (and technology) Science - knowledge attained through study...

Post on 13-Jan-2016

228 views 0 download

Tags:

transcript

Chapter 1

Science&

Technology

Science: (and technology)

•Science - knowledge attained through study or practice or knowledge covering general truths of the operation of general laws, especially as obtained and tested through the scientific method [and] concerned with the physical world•Technology - and knowledge of tools, techniques, and crafts.

Science: (and technology)

•Has helped societies throughout history to advance and even thrive above other cultures.

•organized way of investigating the natural world and put resources to a beneficial use.

Laws and Theories

Theories: explanation based on observations and investigations. Theories can change or be discarded if new information is discovered

Developed from a hypothesis that is proven over and over

Laws and Theories

Scientific Law: Statement about things that occur in nature and seem to be true all of the time, do not explain why or how

Law of gravity – two masses attract each other

Scientific Method: a logical method to solve ANY

problem.

Scientific Method

State the Problem = needs to be well defined

Gather information = (Research the Problem) become an expert on the problem

Form the Hypothesis = through research; an educated guess at a solution to the problem

Test = run a controlled experiment to test the hypothesis by Recording & analyzing data

State Your Conclusion = evaluate the success of the hypothesis. Adjust and Retest as necessary

Research and Hypothesis

Research – gather information about past observations and experiments so that experiments and errors are not repeated

Hypothesis – an educated guess that is testable

Testing the HypothesisFollows a procedureTrials = number of times the experiment

was run. Needs to be a high number to add credibility to the work

Variables = conditions that change during the experiment & factors being tested– independant variable = condition(s) you change – dependent variable = condition(s) that is changed

as a RESULT of what you did *On a Graph = dependant variable goes on the y-

axis, independent variable on the x-axis

Specimen Groups

Control Group = a group that had NO changes in their conditions. Used to set what is NORMAL in order to make comparisons

Experimental Group = group(s) that have the experimental change (independant variable)

Data

Record and analyze dataCarefully review all of the data you

have collected from your experiment.

Use charts and graphs to help you analyze the data and patterns.

Conclusions

Communicate your results– Explain whether the data supports your

hypothesis – Acknowledge any deviations from what you

expected – Derive conclusions, based on your findings– Relate your findings to earlier work in the

same area (if you can) – Explore the implications of your findings

90 mice are run through a maze to get

the average for that maze.

5 minuteswas the

average (all 90 mice)

30 miceControl Group

NO MUSIC

30 miceExperiment Group

ROCK MUSIC

30 miceExperimental Group

CLASSICALMUSIC

Music, Mice and a Maze

Questions

Name the variables.What time MUST the control group have

in order to declare any results as valid?Why must all 3 groups get the exact

amount of food & water?What is the purpose of the maze?What are your predictions?

Actual Results

0

5

10

15

20

25

30

TIME (in minutes, mins.)

ControlGroupExperimental(Classical)

Experimental(Rock)

Prediction and Inference

Statement about the way things will happen in the future, often but not always based on experience or knowledge.

process of drawing a conclusion by applying logic and facts to observations or hypotheses

Models

Representation of an idea, event or object to help people better understand it

Can be physical or computer simulations

Measurement

Standards of MeasurementsAccurate measurements are needed

to make an experiment valid. Standards are exact quantities

(amounts) that people agree upon for comparison.

Measurement is represented by a number and a unit.

Measurement Systems2 types

1. English system of measurement– a. Volume (gallon)– b. Mass (pound)– c. Length (foot)

2. Metric System (International System of Units)– Base Units

Volume (liter)Mass (gram)Length (meters)Time (seconds)Temperature (Kelvin)

SI units

The SI Units are used by scientists and all but 2 countries in the world. The units have prefixes that are used to represent what multiple of ten is being used.

Kangaroos hopping down backwards drinking chocolate milk!

Kilo- 1000 Hecta- 100 Deca- 10 Base Unit- 1 Deci- 1/10 Centi- 1/100 Milli- 1/1000

Multiples of ten are used so that conversions are easily made between each unit.

Conversions

Going up the stairs – move decimal to left for every stair you move

Going down the stairs – move decimal to the right for every stair you move

20 dag = ______ mg3 m = ______ cm1500 mL = ______hL2.8 km = ______dm

Measuring Distance

Length is the distance between two points. You have to choose a unit to measure in that will be most appropriate.

Measuring Volume

Volume is the amount of space that is occupied by an object.

Volume of a rectangle= Length x Width x Height

Unit would be the unit³ Example: cm³

How do you measure the volume of a liquid? You have to measure the capacity of the container.

1 cm³ = 1 mL

Measuring Matter

Mass is the measurement of the quantity of matter in an object. Matter takes up space.

Density is the mass per unit volume of a material

Density = Mass Volume

Measuring Time and Temperature

Time is the interval between two events measured in seconds.

Temperature is measured in Kelvin (K).

Freezing point of Water is 0ºCBoiling point of water is 100ºC0.0K is the coldest possible (known

as absolute zero)Water freezes at 273K and boils at

373K.

Communicating with Graphs

A graph is a visual display of information or data.

Types: 1. Line – Shows the relationship

between independent and dependent variable

x-axis= (horizontal) independent variable

y-axis= (vertical) dependent variable

Line Graph

Bar– useful to show comparisons or

numerical dataA word or category or a number

Circle– Fixed quantity is broken down into

parts- Percentages

Scientific Notation*from standard notation to

scientific notation1. Write # between 1 and 102. Write (x10)3. Count number of spaces the

decimal moved and write it as an exponent on the ten

4. Positive exponent if moved left (making the entire number smaller)

5. negative exponent if moved right (making the entire number larger)

*From Scientific Notation to Standard

1) For positive exponent move decimal number of spaces to make the number bigger

2) For negative exponent move decimal number of spaces to make number smaller