1. MOTION

2. M1. WHAT IS MOTION? Motion occurs whenever something changes position. To tell if something is changing position, you need a point of reference.

3. M2. WHAT IS THE DIFFERENCE BETWEEN DISTANCE AND DISPLACEMENT? Distance is how far something has traveled or moved. Displacement is the difference between where you start and where you end.

4. M3. HOW DO YOU MEASURE THE SPEED OF AN OBJECT? WHAT ARE SOME COMMON UNITS? Speed is the distance an object travels in one unit of time Speed is often measured in: Meters per second, miles per hour, etc.

5. M4. WHAT’S THE DIFFERENCE BETWEEN AVERAGE AND INSTANTANEOUS SPEED? Average speed is found by taking the total distance traveled divided by the total time taken. Instantaneous speed is the speed at one exact moment of time – often different than average speed

6. REVIEW QUESTION #1 What do you need in order to tell that something has moved (or something has changed position)?

7. ANSWER You need a point of reference

8. REVIEW QUESTION #2 What is the difference between distance and displacement?.

9. ANSWER Distance is how far somethinghas traveled or moved. Displacement is the difference between where you start and where you end.

10. M5. WHAT IS THE DIFFERENCE BETWEEN SPEED AND VELOCITY? Speed tells you 1) how fast you are going. Velocity tells you 1) how fast you are going AND 2) what direction you are traveling.

11. M6. ACCELERATION Acceleration is the change in velocity divided by the time it takes for the change to occur.

12. M7. WHAT IS THE DIFFERENCE BETWEEN POSITIVE AND NEGATIVE ACCELERATION? Positive acceleration means that the object is increasing in speed. A negative acceleration means that the object is decreasing in speed. Sometimes the word deceleration is used to mean negative acceleration (slowing down).

13. M8. WHAT IS MASS? Mass is the amount of matter in an object. The more mass an object has the more INERTIA it has.

14. M9. WHAT IS INERTIA? Inertia is the resistance of an object to a change in motion. Objects at rest stay at rest unless acted upon by an outside force. Objects in motion stay in motion unless acted upon by an outside force.

15. M10. WHAT IS MOMENTUM? Momentum is a measure of how hard it is to stop an object. Momentum is the mass of an object times it's velocity. The bigger an object is (more mass) and the faster it is moving, the more momentum it has.

16. M11. THE LAW OF THE CONSERVATION OF MOMENTUM When objects collide, the total momentum remains constant. No momentum is lost unless friction is present.

17. MOMENTUM PRACTICE If the truck has a mass of 2,000 kilograms, what is its momentum? (v = 35 m/s) Express your answer in kg·m/sec.

19. If the car has a mass of 1,000 kilograms, what is its momentum? (v = 35 m/s)

21. An 8-kilogram bowling ball is rolling in a straight line toward you. If its momentum is 16 kg·m/sec, how fast is it traveling?

23. A beach ball is rolling in a straight line toward you at a speed of 0.5 m/sec. Its momentum is 0.25 kg·m/sec. What is the mass of the beach ball?