Motion and Forces study Guide Completion Complete each statement. 1. The motion of an object looks different to observers in different. 2. The SI unit for measuring is the meter. 3. The direction and length of a straight line from the starting point to the ending point of an object s motion is. 4. Displacement and velocity are examples of because they have both magnitude and direction. 5. The sum of two or more vectors is called the. 6. Speed is measured in units of. 7. A car s speedometer measures. 8. is the equation that defines. 9. A constant slope on a distance-time graph indicates speed. 10. The difference between speed and velocity is that velocity indicates the of motion and speed does not. 11. A distance-time graph indicates an object moves 20 km in 2 h. The average speed of the object is km/h. 12. Because its is always changing, an object moving in a circular path experiences a constant change in velocity. 13. A moving object does not if its velocity remains constant. 14. Freely falling objects accelerate at 9.8 m/s 2 because the force of acts on them. 15. The velocity of an object moving in a straight line changes at a constant rate when the object is experiencing constant. 16. The acceleration of a moving object is calculated by dividing the change in by the time over which the change occurs. 17. Accelerated motion is represented by a(an) line on a distance-time graph. 18. A car that increases its speed from 20 km/h to 100 km/h undergoes acceleration.
19. is how fast a velocity is changing at a specific instant. 20. A push or pull is an example of a(an). 21. The type of force measured by a grocery store spring scale is. 22. The sum of all the forces acting on an object is called the. 23. If the forces acting on an object produce a net force of zero, the forces are called. 24. The force that opposes the motion of objects that touch as they move pass each other is called. 25. It usually takes more force to start an object sliding than it does to keep an object sliding because static friction is usually than sliding friction. 26. The two forces acting on a falling object are gravity and. 27. When a falling object reaches terminal velocity, the net force acting on it is. 28. The drag force acting on an falling sky diver is also known as. 29. The path of motion of a thrown javelin is an example of motion. 30. The tendency of an object to resist any change in its motion is called. 31. During a head-on auto collision, causes a passenger in the front seat to continue moving. 32. The force of gravity acting on an object is the object s. 33. If a golf ball and bowling ball are rolling at the same speed, the ball has greater momentum. 34. When you push on a wall, the pushes back on you. 35. The universal force that is most effective over the longest distances is. Short Answer 36. A child rolls a ball 4 m across a room. The ball hits the wall and rolls halfway back toward the child. Using vector addition, calculate the ball s displacement. 37. Bus A travels 300 m in 12 s. Bus B travels 200 m in 12 s. Both vehicles travel at constant speed. How do the distance-time graphs for these two speeds differ?
38. What is the significance of the slope in a distance-time graph? 39. What types of changes in motion cause acceleration? 40. In the equation for acceleration,, how can you describe acceleration if the numerator is negative? 41. What information does the slope of a speed-time graph provide? 42. The slope of the curve at a single point on a distance-time graph of accelerated motion gives what information? 43. What is the direction of the net force on a falling sky diver before she reaches terminal velocity? After she is falling at terminal velocity? 44. How can you double the acceleration of an object if you cannot alter the object s mass? 45. During a collision, a seat belt slows the speed of a crash-test dummy. What is the direction of the net force exerted by the seat belt compared to the direction of the dummy s motion? 46. What law states that if no net force acts on a system, then the total momentum of the system does not change? 47. A billiard ball with a momentum of 20 kg m/s strikes a second ball at rest and comes to a complete stop. What is the change in momentum of the second ball? 48. Compare the speed of a moving golf ball with the speed of a moving bowling ball if both balls have the same amount of momentum. 49. One end of a bar magnet attracts one end of a second bar magnet. What will happen if the second bar magnet is reversed? 50. What is the primary cause of Earth s ocean tides? Speed/Velocity/Acceleration/Distance/Displacement Problems 1.A car travels at 12m/s for 3.5 m minutes. How many meters did the car travel? 2.A person runs 200m in 21 seconds. What is the person s speed in m/s? In mph? 3.A person rides a bike at 18mph for 40 min. How far did they travel? 4.A car is sitting at a stop sign. If it accelerates to 55mph in 7 seconds, what is the acceleration of the car? 5.A person driving a car at 90mph sees a police officer and slams the breaks, slowing the car to a speed of 65mph in 3s. What is the acceleration of the car? 6.A runner does 6 laps around a 400m track. What is her distance? What is her displacement? 7.John leaves his house and walks 5 miles west, 5 miles north, and 5 miles east. What is his distance traveled? What is his displacement? 8.Sara walks 7 Km north and 9 Km East. What is her distance? What is her displacement? Force and Momentum Problems 9.An object is pulled with a force of 50N to the east and 40N to the west. What is the net force on the object? 10.What is the force of an object that has a mass of 72 Kg and is accelerating at 23m/s/s?
11.What is the mass of an object that is producing 200N of force and accelerating at 5m/s/s? 12.What is the acceleration of an object that produces 35N of force and has a mass of 32Kg? 13.What is the force required to cause a 10Kg object to increase its velocity from 2m/s to 30 m/s over a period of 4 seconds? 14.What is the momentum of a 22 Kg object that has a velocity of 4 m/s? 15.What is the mass of an object that has a momentum of 45 Kg m/s and a velocity of 600m/s 16.What is the velocity of an object that has 38 Kg m/s of momentum and a mass of 3Kg?