1. Average Velocity

2. Speed versus Velocity
Speed (v): The distance an object travels during a given time interval. Does not include distance (Scalar) -eg 100km/h Velocity (v): The displacement of an object during a given time interval -eg 100km/h [N]

3. Speed versus Velocity
Same speed different velocity Note: Speed is the same

4. Speed versus Velocity
Same speed different velocity Note: Speed is the same velocity is different (+, -)

5. Velocity
Velocity and Displacement: Velocity always travels in the same direction as displacement. SI units = m/s

6. Calculating Velocity using Slope
Velocity = Slope of a position time graph Slope = Δd = (df - di) Δt (tf - ti)

7. Example:
Slope = Δd = (df - di) = (60m - 0m) = Δt (tf - ti) (10s – 0s)

8. .
Slope = Δd = (df - di) = (60m - 0m) = 60m = 6m/s Δt (tf - ti) (10s – 0s) 10s

9. .
Slope = Δd= (df - di) = (-40m - 60m) = Δt (tf - ti) (40s – 15s)

10. .
Slope = Δd= (df - di) = (-40m m) = -100m = -4m/s
Δt (tf - ti) (40s – 15s) s

11. .
Slope = Δd= (df - di) = (0m m) = 40m = 2.7m/s
Δt (tf - ti) (55s – 40s) s

12. - Try calculating the velocity for the other two slopes
Remember the slope can be either positive negative or zero

13. Average Velocity
Average Velocity (Vav): Because it is almost impossible for something to move in perfect uniform velocity we usually take the average of the velocities in a time interval. Eg, Using a best fit line

14. Converting m/s to km/h
Parts: 1h = 3600s 1km [W] = 1000m [W] Convert 7200s to hours Convert 3 hour to seconds

15. Converting m/s to km/h
Parts: 1h = 3600s 1km [W] = 1000m [W] Convert 600s to hours 7200s X 1h = 2h 3600s Convert 3 hour to seconds

16. Converting m/s to km/h
Parts: 1h = 3600s 1km [W] = 1000m [W] Convert 600s to hours 7200s X 1h = 2h 3600s Convert 3 hour to seconds 3h X 3600s = s 1h

17. .
Converting 6km to m 6km X 1000m = 6000m 1km Convert 27000m to km

18. .
Converting 6km to m 6km X 1000m = 6000m 1km Convert 27000m to km 27000m X 1km = 27km 1000m

19. Converting m/s and km/h
Eg. 55km/h 55km x (1000m) x 1h = 15m/s 1h 1km 3600s Hi Ms. Krom!!