1. MOTION
A review

2. MOTION
Motion = When an object changes position over time when compared with a reference point

3. REFERENCE POINT
Reference point = The object that appears to stay in place

4. Motion = When an object changes position over time when compared with a reference point

5. SPEED
Speed = The rate at which an object moves. Speed depends on the distance traveled and the time taken to travel that distance.

6. Average Speed Average Speed = Total distance Total Time
Example: 360km = 90km
4hrs Hr.

7. Velocity Notes

8. What is velocity?

9. Velocity is
Velocity = Speed + Direction

10. What are some units for velocity?

11. Velocity is expressed as
600 km/min North
8 m/s south
65 mph west

12. When does velocity change?

13. Velocity changes as Speed or Direction changes

14. For example Velocity changes when speed slows down 50 km/min down to

15. For example Velocity changes when speed goes faster 0km/hr north to

16. For example Velocity changes when direction changes 2m/sec up to
2m/sec down

17. To summarize Velocity is speed with direction
Units for velocity always include speed and direction
Velocity can change if the speed or the direction changes.

18. Sample Problem 1
Juan is walking 2 m/s South on a train that is moving 60 m/s North. What is his velocity?

19. Sample Problem
Juan is walking 2 m/s South on a train that is moving 60 m/s North. What is his velocity?
60-2 = 58m/s north

20. Sample problem 2
Jessica walks 3 m/s west to the front of a bus moving 30m/s west. What is her velocity?

21. Sample problem 2
Jessica walks 3 m/s west to the front of a bus moving 30m/s west. What is her velocity?
30 + 3= 33 m/s west

22. Sample problem 3
Which of these can I change without changing the velocity?
Speed
Direction
Reference point