1. Motion Movin and Groovin!

2. Frame of Reference Movement from a fixed point. Movement is relative to a fixed point. Is she moving towards you or away from you?

3. Frame of Reference What is the space shuttle’s frame of reference? What is the race car’s frame of reference?

4. Frame of Reference Are we moving right now??? Yes! The Earth rotates at about 1000 miles per hour.

5. Speed Speed is a measure of how fast something is moving. Speed = Distance Time

6. Average Speed On trips our speeds usually fluctuate. The average speed is usually much different than our instantaneous speeds. Average Speed = total distance traveled total time

8. Example If a cheetah runs 25m/s, how far will the cheetah run in 10 seconds? S=d/td= speed x time d= 25m/s x 10s = 250m

9. Velocity What’s the difference between speed and velocity? Speed = how fast something moves (30 m/s) Velocity = how fast something moves in a direction (30 m/s east)

10. Velocity velocity = distance time

11. Constant Velocity Constant velocity = constant speed and constant direction Does velocity change when a car goes around a curve?

12. If a train and a car are traveling the same path at the same speed, which is more difficult for Superman to stop? Why?

13. Momentum Objects with more momentum would be more difficult to stop. Momentum depends on velocity and mass. momentum = mass x velocity p = m x v

15. Acceleration Any change in velocity is known as acceleration. Acceleration = final velocity – initial velocity time a = Δ v Δ t

16. Acceleration What does an acceleration tell you? If the acceleration is small, the speed is increasing gradually. If the acceleration is great, the object is speeding up rapidly. Negative acceleration (deceleration) means that the object is slowing down.

17. Acceleration Acceleration is determined by a velocity- time graph

18. Practice Problems Natalie accelerates her skateboard along a straight path from 0 m/s to 4.0 m/s in 2.5 s. What is her acceleration? a = 4.0 m/s – 0 m/s 2.5 s a = 1.6 m/s 2

19. Practice Problems A turtle swimming in a straight line toward shore has a speed of 0.50 m/s. After 4.0 s, its speed is 0.80 m/s. What’s the turtles average acceleration? a = 0.80 m/s – 0.50 m/s 4.0s a = 0.075 m/s 2

20. Force What is force? Force is the change in velocity or acceleration of an object.

21. Force What is a balanced force? Forces that cancel each other out to produce zero net force.

23. Force What is an unbalanced force? Forces that combine to cause an object to accelerate.

25. Friction What is friction?How does it effect motion? Friction is the force between two objects in contact that opposes the motion of either object.

26. Friction