1. MOTION, SPEED, VELOCITY, MOMENTUM, and ACCELERATION

2. What is motion?

3. Motion is a change in the position or location of an object.

4. How can you tell a person or an object is in motion?

5. How can you tell a person or an object is in motion? The person or object must change their location with respect to a reference point. (Reference points are stationary.)

6. What object(s) could serve as reference point(s) in the picture below?

9. The position of an object is the distance between that object and the reference point.

10. What are the two types of motion?

11. The motion of an object can either be at a constant velocity or a changing velocity. A change in velocity is known as acceleration.

12. The two terms velocity and speed are very similar. Speed refers to how fast an object is moving. Velocity is speed in a direction.

13. Classify the following as either speed or velocity.

14. Speed or Velocity A truck travels at 64 mph due north on interstate 65.

15. Speed or Velocity A truck travels at 64 mph due north on interstate 65.

16. Speed or Velocity The pitcher threw the ball towards the batter. The ball was traveling 88 mph.

17. Speed or Velocity The pitcher threw the ball towards the batter. The ball was traveling 88 mph.

18. Speed or Velocity The driver drove very slowly. The truck moved at 5 mph.

19. Speed or Velocity The driver drove very slowly. The truck moved at 5 mph.

20. Speed or Velocity The waves rushed towards the beach at 12 mph.

21. Speed or Velocity The waves rushed towards the beach at 12 mph.

22. Speed or Velocity

24. The dragonfly flew at 38 km/hr.

25. Speed or Velocity The dragonfly flew at 38 km/hr.

26. Speed or Velocity The cross country runner ran the 5 km race in 22 minutes..

27. Speed or Velocity The cross country runner ran the 5 km race in 22 minutes..

28. Quantities that only have a number or magnitude or size are referred to as scalar. Speed is a scalar quantity.

29. Quantities that have a number or magnitude or size and a direction are referred to as vector. Velocity is a vector quantity. Acceleration is also a vector quantity.

30. Speed or Velocity Equation: v = d t where v is either speed or velocity d is distance t is time

31. Acceleration Equation: a =  v t where a is acceleration v is velocity or speed t is time

32. The metric system is now called the SI System. SI stands for International System of Units (abbreviated SI from the French le Système international d'unités)French

33. Symbols and SI Units speed or velocity m/sec or m/s acceleration m/sec/sec or m/sec 2 distance m time sec or s

34. Acceleration Facts: - is a change in velocity. - is positive if velocity is increasing. - is negative if velocity is decreasing (also called deceleration). - occurs even when the speed stays the same and only the direction changes.

35. Does acceleration occur in the following situations?

36. Acceleration: Yes or No The red car is traveling at 20 mph on the winding mountain road.

37. Acceleration: Yes or No The red car is traveling at 20 mph on the winding mountain road.

38. Acceleration: Yes or No A camel walks a straight line at a constant speed.

39. Acceleration: Yes or No A camel walks a straight line at a constant speed.

40. Acceleration: Yes or No The car exited the freeway at speed of 55 mph and came to a stop before turning right onto a service road.

41. Acceleration: Yes or No The car exited the freeway at speed of 55 mph and came to a stop before turning right onto a service road.

42. Acceleration: Yes or No The space shuttle can travel at a speed of 17,500 km/hr.

43. Acceleration: Yes or No The space shuttle can travel at a speed of 17,500 km/hr.

44. Acceleration Equation: a =  v or v f - v i t t where  v is delta v or change in velocity and means final velocity (v f ) minus initial velocity (v i ).

45. Distance vs. Displacement Distance is how far an object travels. It is considered a scalar quantity. Displacement is how far an object is from the starting point. It is considered a vector quantity.

48. 20 meters 15 meters 17 meters If the boy walked to the truck and then to the scooter, what was his distance?

49. 20 meters 15 meters 17 meters If the boy walked to the truck and then to the scooter, what was his distance? 15 m + 17 m = 32 m

50. 20 meters 15 meters 17 meters If the boy walked to the truck and then to the scooter, what was his displacement? 20 m

51. The raccoon walked 5 meters west and stopped. Then he walked 2 meters more due west. A. What is the raccoons displacement? B. What is the raccoons distance?

52. The raccoon walked 5 meters west and stopped. Then he walked 2 meters more due west. A. What is the raccoons displacement? 7 m B. What is the raccoons distance? 7 m 5 meters2 meters

53. A deer walks forward 12 meters west and then backs up 12 meters east. A. What is the distance the deer covered? B. What is the displacement?

54. A deer walks forward 12 meters west and then backs up 12 meters east. A. What is the distance the deer covered? 12 m + 12 m = 24 m B. What is the displacement? Since the deer ended up where it started, the displacement is zero.

55. Momentum - is the product of an object’s mass and velocity. - has the symbol p - is a vector quantity - equation p = m  v where p is momentum, m is mass in kilograms, and v is velocity in meters/second - has the unit kg  m s

56. Which has more momentum? (momentum = mass  velocity) Baseball A 0.62 kg 5.3 m/s Baseball B 0.62 kg 4.1 m/s

57. What is the momentum of baseball A? (momentum = mass  velocity) Baseball A 0.62 kg 5.3 m/s p = m  v p = (0.62 kg)(5.3 m/s) p = 3.29 kg  m s

58. Which has more momentum? (momentum = mass  velocity) An empty dump truck traveling 35 mph An dump truck full of rocks traveling 35 mph

59. Which has more momentum? (momentum = mass  velocity) An empty dump truck traveling 35 mph An dump truck full of rocks traveling 35 mph

60. To Be Continued…