Conceptual PhysicsMr EvansRm 714

Objectives•Define physics•List the 6 branches of physics•Define model•Explain the importance of models•Describe how models are used

What is Physics?

The goal of physics is to understand the rules that

govern the way the natural world behaves.

I. The Nature of Physics and Learning Physics?

• Physics is a process of learning about the physical world by finding ways to make sense of what we observe and measure.

• Learning physics requires that you continually compare and contrast your observations to your intuitions and expectations.

• Physics helps you make sense of the physical world.

• Physics is the refinement of common sense. It is more than common sense.

• Physics is common sense made consistent by continued reference to both theory and experiment.

• Physics is not a jumble of separate equations to be memorized.

The key to understanding physics is to learn fundamental relationships and to apply them to new scientific problems.

Conclusion…

Physics is defined as the study of matter and energy…it is the study of everything.

True/False

1.Temperature is the same thing as heat

FALSE

True/False

6. To produce heat, the sun burns hydrogen in a combustion reaction.

FALSE

True/False

8.If a feather and hammer are dropped on the Moon at the same time from the same height they will hit the Moon’s surface at the same time.

TRUE

True/False

9. The Moon has no gravity.

FALSE

True/False

10. Mass and weight have essentially the same meaning. To increase the weight of an object requires an increase in the mass of the object.

FALSE

True/False

12. An astronaut orbits the Earth 500 miles above its surface. She appears to be weightless because there is virtually no gravitational force on her.

FALSE

True/False

22. If a car hits a tree, the car’s occupants (assume no seat belts or air bags) will be violently thrown forward due to a force created by the car seats.

False

True/False

26. Iron can exist as a gas.

TRUE

What are the branches of physics?

1.Mechanics-The study of motion and its causes…kinematics and dynamics.

2.Thermodynamics

-The study of heat and temperature.

Thermo = heat

3. Waves and Optics

-the study of specific types of wave motion and light

4.Electromagnetism

-The study of electricity and magnetism

Remember this by breaking the word apart.

electro (electricity) + magnetism = electromagnetism

5. Modern Physics

Include the areas of 1.Relativity -The study of high speed particles.

2. Quantum Physics and Atomic Physics -

The study of the nature of matter and light at the microscopic level.

What do you think?

Which areas of physics deal with the following?

1. Cooling off on a hot day by diving into a swimming pool.

2. Wearing a pair of sunglasses.

3. Building a louder stereo system in your car.

4. Bungee jumping

5. Playing in the high school band

How is physics distinct from chemistry, biology or other

sciences?

Physics does not, nor is it supposed to, describe reality

exactly as it is. Part of the art of solving

physics problems or analyzing phenomena is

choosing the right model.

Lesson Objectives

At the end of the lesson you should be able to:

1. Define model as it relates to science.2. Explain how models are used in

science.3. List 3 types of models also known as

representations used in physics.4. Provide examples of how each

representation is used in physics.

Models: A Vehicle for Understanding

• Understanding Physics begins with building models…mentally, that is!

• Modeling, in science, is a skill that takes some practice and experience to acquire.

Model Building involves:

• Simplifying the situation• Isolating the essential features of

that situation• Developing a set of relationships

(usually in the form of equations) that provides an adequate, although not perfect, description of reality.

Think/Pair/Share

Consider the phrase, “The quick brown fox jumped over the lazy dog.” Which details of this situation would a physicist who is modeling the path of a fox ignore?

What kinds of models will you use in this course?

1. Pictures (pictorial representation)- shows a sketch of the situation.

What kinds of models will you use in this course?

2. Graphs (graphical representation)- graphs are very useful for identifying trends and drawing conclusions.

What kinds of models will you use in this course?

3. Math (mathematical representation) – demonstrates relationships in very brief terms