2. L INEAR M OTION

3. F AST speed depends on distance and time average speed uses total distance and total time

4. F RAME OF R EFERENCE speed is relative FOR is something to compare speed to How fast are you moving now? Earth is rotating at 1,000 mph

5. F RAME OF R EFERENCE Earth is orbiting sun at 66,000 mph Everything in universe is moving

6. F RAME OF R EFERENCE So, if you drive 55 mph, you are going 55mph relative to the earth Universe speed limit: speed of light 3 x 10 8 m/s Is car moving?

7. V ELOCITY Scalar vs. Vector scalar: measures only the amount ex: temperature, area, distance traveled vector: measures both amount and direction vector: scalar and direction ex: weight in which direction is weight directed?

8. D ISPLACEMENT speed = distance / time velocity = displacement / time distance: log of total miles traveled displacement: change in position displacement: distance from start to end arrows mean they are vectors distance displacement

9. Time to Practice Go to pg. 295

10. G RAPHING R ULES 1.Use a ruler (straightedge)! 2.Label your axes! (units in parentheses) time is always below 1.Use a ruler (straightedge)! 2.Label your axes! (units in parentheses) time is always below Time (s) Variable Unit Distance (m)

11. G RAPHING R ULES F3.Title the graph! F(Y vs. X) F3.Title the graph! F(Y vs. X) Distance vs. Time Time (s) Distance (m)

12. G RAPHING R ULES F4.SCALE. FStretch out your axes! F4.SCALE. FStretch out your axes!

13. G RAPHING R ULES F5. Use a Pencil!! F6. Do not just connect the dots! Line of best fit curve: smooth line: ruler they might not touch dots F5. Use a Pencil!! F6. Do not just connect the dots! Line of best fit curve: smooth line: ruler they might not touch dots

14. G RAPHING R ULES FDrawing tangent lines Fdrawn at a point F“balance” ruler on curve F perpendicular with normal FDrawing tangent lines Fdrawn at a point F“balance” ruler on curve F perpendicular with normal Distance vs. Time Time (s) Distance (m) Fmake it long enough to find the slope Ahh. Just right!

15. G RAPHING

16. M OVIES And now for a short movie

17. E UREKA : I NERTIA

18. E UREKA : M ASS

19. E UREKA : S PEED

20. L ABETTE Graphing Motion pg. 305 Graphing Motion pg. 305

21. A CCELERATION acceleration  the rate of change of velocity  final velocity  initial velocity refers to speeding up and slowing down or… arrows mean …

22. E XAMPLE A car moving at 20 m/s comes to a stop in four seconds. What was the car’s acceleration? Given: Want:

23. E XAMPLE solve for acceleration said “negative five meters per second per second” negative acceleration means… slowing down

25. A CCELERATION you “feel” speed when you accelerate This includes speeding up, slowing down and sharp turns at constant speed! All three are accelerations

26. E UREKA : A CCELERATION I

27. S PEED VS. T IME G RAPHS look at the slope units are m/s/s=m/s 2 acceleration! same answer as example

28. Speed vs. Time Graphs So, to summarize the graphs: For distance vs. time: slope = speed For speed vs. time: slope = acceleration area under line = distance covered

29. E UREKA : A CCELERATION II

30. F REEFALL freefall  objects moving under only force of gravity terminal velocity  when air resistance becomes equal to gravity due to gravity = g g = 9.8 m/s 2

31. F REEFALL let’s look at the motion of three objects one dropped from rest one thrown downwards one thrown upwards All of these motions are types of… freefall!

32. F REEFALL let’s look at the motion of three objects one dropped from rest one thrown downwards one thrown upwards All of these motions are types of… freefall!

33. E UREKA : G RAVITY

34. L AB Acceleration due to Gravity pg. 314 Acceleration due to Gravity pg. 314

35. P UTTING IT TOGETHER Let’s use what we know about graphs to make two more formulas. Let’s look at the graph from t i to t f

36. P UTTING IT TOGETHER each time matches up with a velocity First velocity is v i and last is v f vivi vivi vfvf vfvf

37. P UTTING IT TOGETHER To find distance: area under the line two shapes: triangle and rectangle vivi vivi vfvf vfvf

38. P UTTING IT TOGETHER d = area of rectangle + area of triangle area of rectangle area of triangle vivi vivi vfvf vfvf

39. P UTTING IT TOGETHER we now have a connection between a and d

40. P UTTING IT TOGETHER solve for t from first a equation substitute into second a equation a little fancy algebra and… nice if you do not have t

41. P UTTING IT TOGETHER use equation 1 only if acceleration is zero use equations 2-4 only if constant acceleration

42. P UTTING IT TOGETHER notice there are no arrows they are still all vectors

43. P UTTING IT TOGETHER vectors mean that direction is important ex. positive for up, negative for down

44. E XAMPLE A spear is thrown down at 15 m/s from the top of a bridge at a fish swimming along the surface below. If the bridge is 55 m above the water, how long does the fish have before it gets stuck? Given: Want: why negative?

45. E XAMPLE Which equation has v i, d, a and t ? Eqn 3 works, but…you would need quadratic (bleh!) Eqn 2 would work if we had v f. Eqn 4 can get us v f !

46. E XAMPLE First, eqn. 4 positive or negative?

47. E XAMPLE solve for t in eqn 2. substitute v f into eqn 2.

48. C HECK Y OURSELF Turn to pg. 321