GET READY TO TAKE NOTES

1. GET READY TO TAKE NOTES

2. Sunday, January 5, 2020 Come on people, this is not rocket science

3. Oh, Wait

5. Motion Chapter 6 Section 1

6. What is Motion?A Change in Position

7. Motion…

8. Distance and Displacement • Distance – How far you have traveled • Displacement – How far away it is

9. Distance Verses Displacement

10. Texas Motor Speedway 1.5 mile oval

11. Distance Vs Displacement • If a driver goes 200 laps starting at the start line and finishing at the finish line; • What is the distance traveled? • What is the displacement?

12. Answer • The distance traveled is 300 miles (200 laps X 1.5 miles per lap) • The displacement is zero. (The driver is at the same location he started from.)

13. Relative motion • An object in motion changes position • This position is in relation to another object

15. Speed • Two factors determine speed • Distance traveled • Time spent traveling • Examples; • Miles per hour • Feet per second • Meters per second • Speed is distance divided by time

16. Speed

17. So…

18. And…

19. Constant Speed • Cruise control set at 60 MPH • Always at the same speed • Covering one mile every minute • Same distance each time interval • Key term CONSTANT!

20. Average Speed • Total time divided by total distance. • RMS to Six Flags 20 minutes. • 13 miles 20 minutes. • Constant Speed? • No… stop signs, freeways, city streets. • Different rates of speed. • This is average speed.

21. What is Our Speed? • 13 miles • 20 minutes = .33 hours • 13 Miles/0.33 Hours = 39.4 M/H or MPH

22. Velocity • What is the difference between velocity and speed? • Velocity has direction, speed does not • Remember displacement and distance? • Speed is distance divided by time • Velocity is displacement divided by time

23. OR… Δ (delta) is science speak for change in something

24. Calculation • A Sprinter runs a 100 meter race in 10 seconds • What is his average velocity? • Distance is 100 meters • Time is 10 seconds • 100Meters ÷ 10 Seconds = 10M/S

25. Texas Motor Speedway 1.5 mile oval

26. Velocity vs. Speed • If a driver goes 200 laps starting at the start line and finishing at the finish line in 2 Hours • What is his speed? • What is his velocity?

27. Answer • Speed • 300 Miles (distance)/2 Hours = 150 MPH • Velocity • 0 (displacement)/2 Hours = 0MPH

28. Acceleration • A change in velocity • Speeding up or slowing down • Acceleration equals final velocity minus initial velocity divided by time

29. OR

31. Calculation • A skateboarder goes from 2 m/s to 8 m/s in 12s. What is his acceleration • Initial velocity = 2m/s • Final velocity = 8m/s • Time is 12s • So ΔV = 8m/s - 2m/s = 6m/s • 6ms ÷ 12s = 0.5m/s/s or 0.5m/s2

32. Calculation • Same skateboarder hits a mud hole and goes to a complete stop in 1s. What is his acceleration • Initial velocity = 8m/s • Final velocity = 0m/s • Time is 1s • So… ΔV = 0m/s - 8m/s = -8m/s • -8ms ÷ 1s = -8m/s/s or -8m/s2

33. Turning • Remember velocity has direction. • So a change in direction is also acceleration

34. Texas Motor Speedway 1.5 mile oval

35. Question • If a racecar is traveling at a constant speed at Texas Motor Speedway, is it accelerating? • Yes, on the turns.

36. Three Ways to Accelerate • Increase velocity • Decrease velocity • Change direction

37. THE END