1. Relative Velocity 1

2. Previously we stated that all motion is relative 2

3. Relative Velocity Previously we stated that all motion is relative This includes velocity 3

4. Relative Velocity Previously we stated that all motion is relative This includes velocity The velocity of an object is compared to a reference point. 4

5. Relative Velocity Previously we stated that all motion is relative This includes velocity The velocity of an object is compared to a reference point. Frequently that reference point is the observer. 5

6. The hobo is moving 1.2m/s in the boxcar. (relative to the boxcar) The outside observer see the hobo’s motion as 16.5m/s relative to the ground. 6

7. Is the person in the car standing still? 7

8. Relative Velocity 8

9. Velocity of the bowling ball is relative to the bowling alley 9

10. Relative Velocity Velocity of the bowling ball is relative to the bowling alley The bowling alley is the frame of reference 10

11. Relative Velocity Velocity of the bowling ball is relative to the alley When moving in a straight line, vector subtraction can be used to find the relative velocity of an object 11

12. Relative Velocity B represents the bowling ball 12

13. Relative Velocity B represents the bowling ball A represents the bowling alley 13

14. Relative Velocity B represents the bowling ball A represents the bowling alley Velocity of the ball is relative to the bowling alley 14

15. B represents the bowling ball v = 3.0m/s R A represents the bowling alley v = 0.0 m/s The velocity of B relative to A is written as V BA = V B – V A 3.0 m/s,R - 0.0 m/s = 3.0m/s,R ball This is from the perspective of the alley Relative Velocity 15

16. Relative Velocity B represents the bowling ball v = 3.0m/s R A represents the bowling alley v = 0.0 m/s The velocity of A relative to B is written as V AB = V A – V B 0.0 m/s -3.0 m/s,R = -3.0m/s,R ball This is from the perspective of the ball 16