Centripetal Force Review. 1. The graph given shows the weight of three objects on planet X as a function of their mass.

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1 Name: ate: 1. The graph given shows the weight of three objects on planet X as a function of their mass. 3. If the circular track were to suddenly become frictionless at the instant shown in the diagram, the car s direction of travel would be A. toward E. toward N. toward W. a clockwise spiral 4. ase your answer(s) to the following question(s) on the information and diagram below. The acceleration due to gravity on planet X is approximately A m/s m/s 2 A 1200-kilogram car traveling at a constant speed of 9.0 meters per second turns at an intersection. The car follows a horizontal circular path with a radius of 25 meters to point P m/s m/s 2 2. ase your answer(s) to the following question(s) on the information and diagram below. A kilogram car is driven clockwise around a flat circular track of radius 25.0 meters. The speed of the car is a constant 5.00 meters per second. The magnitude of the centripetal force acting on the car as it travels around the circular path is approximately A N N N N What minimum friction force must exist between the tires and the road to prevent the car from skidding as it rounds the curve? 5. At point P, the car hits an area of ice and loses all frictional force on its tires. Which path does the car follow on the ice? A. A... A N N N N page 1

2 6. ase your answer(s) to the following question(s) on the information and diagram below. A 60.-kilogram car travels clockwise in a horizontal circle of radius 10. meters at 5.0 meters per second. 8. A child is riding on a merry-go-round. As the speed of the merry-go-round is doubled, the magnitude of the centripetal force acting on the child A. remains the same. is doubled. is halved. is quadrupled 9. A ball of mass M at the end of a string is swung in a horizontal circular path of radius R at constant speed V. Which combination of changes would require the greatest increase in the centripetal force acting on the ball? A. doubling V and doubling R. doubling V and halving R The magnitude of the centripetal force acting on the car is. halving V and doubling R. halving V and halving R A. 590 N. 150 N. 30. N. 2.5 N 7. ase your answer(s) to the following question(s) on the information and diagram below. A 1.50-kilogram cart travels in a horizontal circle of radius 2.40 meters at a constant speed of 4.00 meters per second. escribe a change that would quadruple the magnitude of the centripetal force. page 2

3 10. The diagram below represents a block at rest on an incline. 11. The diagram below shows a 5.0-kilogram bucket of water being swung in a horizontal circle of 0.70-meter radius at a constant speed of 2.0 meters per second. Which diagram best represents the forces acting on the block? (F f = frictional force, F N = normal force, and F w = weight.) A. The magnitude of the centripetal force on the bucket of water is approximately. A. 5.7 N. 14 N. 29 N. 200 N 12. A 400-newton girl standing on a dock exerts a force of 100 newtons on a newton sailboat as she pushes it away from the dock. How much force does the sailboat exert on the girl?. A. 25 N. 100 N. 400 N N 13. ase your answer(s) to the following question(s) on the information and diagram below.. A soccer ball is kicked from point P i at an angle above a horizontal field. The ball follows an ideal path before landing on the field at point P f. On the diagram above, draw an arrow to represent the direction of the net force on the ball when it is at position X. Label the arrow F net. [Neglect friction.] page 3

4 14. A 1200-kilogram space vehicle travels at 4.8 meters per second along the level surface of Mars. If the magnitude of the gravitational field strength on the surface of Mars is 3.7 newtons per kilogram, the magnitude of the normal force acting on the vehicle is 19. The diagram here shows a ball projected horizontally with an initial velocity of 20 meters per second east, off a cliff 100 meters high. [Neglect air resistance.] A. 320 N. 930 N N N 15. A 1750-kilogram car travels at a constant speed of 15.0 meters per second around a horizontal, circular track with a radius of 45.0 meters. The magnitude of the centripetal force acting on the car is How many seconds does the ball take to reach the ground? A. 4.5 s. 20 s. 9.8 s. 2.0 s A N. 583 N N N 16. A 60-kilogram astronaut weighs 96 newtons on the surface of the Moon. The acceleration due to gravity on the Moon is A. 0.0 m/s m/s m/s m/s A baseball is thrown at an angle of 40.0 above the horizontal. The horizontal component of the baseball s initial velocity is 12.0 meters per second. What is the magnitude of the ball s initial velocity? A m/s m/s m/s m/s 18. A toy rocket is launched twice into the air from level ground and returns to level ground. The rocket is first launched with initial speed v at an angle of 45 above the horizontal. It is launched the second time with the same initial speed, but with the launch angle increased to 60. above the horizontal. escribe how both the total horizontal distance the rocket travels and the time in the air are affected by the increase in launch angle. [Neglect friction.] 20. uring the flight of the ball, what is the direction of its acceleration? A. downward. upward. westward. eastward 21. A cannon elevated at an angle of 35 to the horizontal fires a cannonball, which travels the path shown in the diagram. [Neglect air resistance and assume the ball lands at the same height above the ground from which it was launched.] If the ball lands meters from the cannon 10 seconds after it was fired, what is the horizontal component of its initial velocity? A. 70 m/s. 49 m/s. 35 m/s. 7.0 m/s 22. If the ball s time of flight is 10 seconds, what is the vertical component of its initial velocity? A. 9.8 m/s. 49 m/s. 70 m/s. 98 m/s page 4

5 23. If the angle of elevation of the cannon is decreased from 35 to 30, the vertical component of the ball s initial velocity will A. decrease and its horizontal component will decrease. decrease and its horizontal component will increase 26. A space probe is launched into space from Earth s surface. Which graph represents the relationship between the magnitude of the gravitational force exerted on Earth by the space probe and the distance between the space probe and the center of Earth? A.. increase and its horizontal component will decrease. increase and its horizontal component will increase 24. The diagram shows two bowling balls, A and, each having a mass of 7.00 kilograms, placed 2.00 meters apart... What is the magnitude of the gravitational force exerted by ball A on ball? A N N N N. 25. On the surface of Earth, a spacecraft has a mass of kilograms. What is the mass of the spacecraft at a distance of one Earth radius above Earth s surface? A kg kg kg kg page 5

6 27. The diagram here represents a mass of 1.0 kilogram traveling at 8.0 meters per second in a circular path of radius 4.0 meters. 31. The diagram represents a kilogram satellite, S, in a circular orbit at an altitude of meters. The orbital speeds of the satellite is meters per second and the radius of the Earth, R, is meters. What is the centripetal acceleration of the object? A. 10 m/sec m/sec m/sec m/sec If the mass of the object is doubled, the magnitude of the centripetal force will be A. one-half as much. twice as much. one-fourth as much. four times as much 29. An object weights 200 newtons at a distance of 100 kilometers above the center of a small uniform planet. How much will the object weigh 200 kilometers above the planet s center? The centripetal acceleration of the satellite shown is closest to A. 9.8 m/s m/s m/s m/s If the altitude of the satellite decreased, its centripetal acceleration would A. decrease. increase. remain the same A. 400 newtons. 100 newtons newtons newtons 30. If the velocity of a car traveling around a circular track doubles, its centripetal acceleration would be 33. The weight of the satellite on the Earth s surface would be A. 560 N. 980 N. 1,900 N. 3,900 N A. 1 2 as great. 2 times greater. 1 4 as great. 4 times greater page 6

7 34. The diagram below represents two satellites of equal mass, A and, in circular orbits around a planet. ompared to the magnitude of the gravitational force of attraction between satellite A and the planet, the magnitude of the gravitational force of attraction between satellite and the planet is A. half as great. twice as great. one-fourth as great. four times as great 35. ase your answer(s) to the following question(s) on the passage and data table blelow The net force on a planet is due primarily to the other planets and the Sun. y taking into account all the forces acting on a planet, investigators calculated the orbit of each planet. A small discrepancy between the calculated orbit and the observed orbit of the planet Uranus was noted. It appeared that the sum of the forces on Uranus did not equal its mass times its acceleration, unless there was another force on the planet that was not included in the calculation. Assuming that this force was exerted by an unobserved planet, two scientists working independently calculated where this unknown planet must be in order to account for the discrepancy. Astronomers pointed their telescopes in the predicted direction and found the planet we now call Neptune. Mass of the Sun Mass of Uranus Mass of Neptune ata Table Mean distance of Uranus to the Sun Mean distance of Neptune to the Sun kg kg kg m m The diagram below represents Neptune, Uranus, and the Sun in a straight line. Neptune is meters from Uranus. alculate the magnitude of the interplanetary force of attraction between Uranus and Neptune at this point. [Show all work, including the equation and substitution with units.] 36. The magnitude of the force the Sun exerts on Uranus is newtons. Explain how it is possible for the Sun to exert a greater force on Uranus than Neptune exerts on Uranus. page 7

8 37. As an astronaut travels from the surface of Earth to a position that is four times as far away from the center of Earth, the astronaut s 41. The accompanying graph represents the relationship between gravitational force and mass for objects near the surface of Earth. A. mass decreases. mass remains the same. weight increases. weight remains the same 38. alculate the magnitude of the centripetal force acting on Earth as it orbits the Sun, assuming a circular orbit and an orbital speed of meters per second. [Show all work, including the equation and substitution with units.] 39. ase your answer(s) to the following question(s) on the information below. Io (pronounced EYE oh ) is one of Jupiter s moons discovered by Galileo. Io is slightly larger than Earth s Moon. The mass of Io is kilograms and the mass of Jupiter is kilograms. The distance between the centers of Io and Jupiter is meters. alculate the magnitude of the gravitational force of attraction that Jupiter exerts on Io. [Show all work, including the equation and substitution with units.] 40. alculate the magnitude of the acceleration of Io due to the gravitational force exerted by Jupiter. [Show all work, including the equation and substitution with units.] The slope of the graph represents the A. acceleration due to gravity. universal gravitational constant. momentum of objects. weight of objects 42. ase your answer(s) to the following question(s) on the information. Projectile A is launched horizontally at a speed of 20. meters per second from the top of a cliff and strikes a level surface below, 3.0 seconds later. Projectile is launched horizontally from the same location at a speed of 30. meters per second. The time it takes projectile to reach the level surface is A. 4.5 s. 2.0 s. 3.0 s. 10. s page 8

9 43. ase your answer(s) to the following question(s) on the information and table below. The weight of an object was determined at five different distances from the center of Earth. The results are shown in the table below. Position A represents results for the object at the surface of Earth. Position istance from Earth s enter (m) Weight (N) A E The approximate mass of the object is A kg. 10 kg. 100 kg. 1,000 kg 44. At what distance from the center of Earth is the weight of the object approximately 28 newtons? A m m m m 45. The diagram below represents the path of an object after it was thrown. 46. A 0.2-kilogram red ball is thrown horizontally at a speed of 4 meters per second from a height of 3 meters. A 0.4-kilogram green ball is thrown horizontally from the same height at a speed of 8 meters per second. ompared to the time it takes the red ball to reach the ground, the time it takes the green ball to reach the ground is A. one-half as great. twice as great. the same. four times as great 47. The acceleration due to gravity on the surface of planet X is 19.6 meters per second 2. If an object on the surface of this planet weighs 980. new-tons, the mass of the object is A kg kg N. 908 N 48. A machine launches a tennis ball at an angle of 25 above the horizontal at a speed of 14 meters per second. The ball returns to level ground. Which combination of changes must produce an increase in time of flight of a second launch? A. decrease the launch angle and decrease the ball s initial speed. decrease the launch angle and increase the ball s initial speed. increase the launch angle and decrease the ball s initial speed. increase the launch angle and increase the ball s initial speed What happens to the object s acceleration as it travels from A to? [Neglect friction.] A. It decreases.. It increases.. It remains the same. 49. A 60.-kilogram physics student would weigh 1560 newtons on the surface of planet X. What is the magnitude of the acceleration due to gravity on the surface of planet X? A m/s m/s m/s m/s 2 page 9

10 50. A car rounds a horizontal curve of constant radius at a constant speed. Which diagram best represents the directions of both the car s velocity, v, and acceleration, a? A.... page 10

11 Problem-Attic format version c EducAide Software Licensed for use by phelipedfernandes@gmail.com Terms of Use at 11/29/ A A A double the speed of car or reduce the radius to.60 m quadruple the mass or double the mass of the cart and halve the radius and more [graph] an arrow at X toward the ground and perpendicular to the ground. The total horizontal distance would decrease; the time in the air would increase F = 2.26x10 17 N Sun is larger in mass.

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