Upon collision, the clay and steel block stick together and move to the right with a speed of

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1 1. A 2.0-kilogram ball traveling north at 4.0 meters per second collides head on with a 1.0-kilogram ball traveling south at 8.0 meters per second. What is the magnitude of the total momentum of the two balls after collision? A) 0 kg-m/s B) 8.0 kg-m/s C) 16 kg-m/s D) 32 kg-m/s 2. Base your answer to the following question on the diagram below which represents carts A and B being pushed apart by a spring which exerts an average force of 50. Newtons for a period of 0.20 second. [Assume friction-less conditions.] Compared to the magnitude of the impulse acting on cart A, the magnitude of the impulse acting on cart B is A) one-half as great B) twice as great C) the same D) four times as great 3. Base your answer to the following question on A 3.0-kilogram steel block is at rest on a friction-less horizontal surface. A 1.0-kilogram lump of clay is propelled horizontally at 6.0 meters per second toward the block as shown in the diagram below. Upon collision, the clay and steel block stick together and move to the right with a speed of 4. A kilogram bullet is fired from a 4.0 kilogram rifle that is initially at rest. If the bullet leaves the rifle with momentum having a magnitude of 20. kilogram meters per second, the rifle will recoil with a momentum having a magnitude of A) 1,600 kg m/s B) 80. kg m/s C) 20. kg m/s D) 0.25 kg m/s 5. Ball A of mass 5.0 kilograms moving at 20. meters per second collides with ball B of unknown mass moving at 10. meters per second in the same direction. After the collision, ball A moves at 10. meters per second and ball B at 15 meters per second, both still in the same direction. What is the mass of ball B? A) 6.0 kg B) 2.0 kg C) 10. kg D) 12 kg 6. Two equal point masses are separated by a distance of 1 meter. If one mass is doubled, the gravitational force between the two masses would be A) one-half as great B) two times greater C) one-fourth as great D) four times greater 7. Compared to the mass of an object at the surface of the Earth, the mass of the object a distance of two Earth radii from the center of the Earth is A) the same B) twice as great C) one-half as great D) one-fourth as great 8. Two objects of equal mass are a fixed distance apart. If the mass of each object could be tripled, the gravitational force between the objects would A) decrease by one-third B) triple C) decrease by one-ninth D) increase 9 times 9. The weight of a 2.0-kilogram mass on planet A is 40 Newtons. The acceleration due to gravity on planet A is closest to A) 20 m/s 2 B) 2.0 m/s 2 C) 80 m/s 2 D) 40 m/s What is the magnitude of the gravitational force between two 5.0-kilogram masses separated by a distance of 5.0 meters? A) N B) N C) N D) N

2 11. The diagram below represents two satellites of equal mass, A and B, in circular orbits around a planet. 15. Base your answer to the following question on on the information below. In an experiment, a kilogram rubber stopper is attached to one end of a string. A student whirls the stopper overhead in a horizontal circle with a radius of 1.0 meter. The stopper completes 10. revolutions in 10. seconds. Compared 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 B and the planet is A) half as great B) twice as great C) one-fourth as great D) four times as great 12. An astronaut weighs newtons on the surface of Earth. What is the weight of the astronaut meters above the surface of Earth? A) 0.00 N B) N C) N D) N 13. What is the magnitude of the gravitational force between an electron and a proton separated by a distance of meter? A) N B) N C) N D) N 14. If the distance between a spaceship and the center of the Earth is increased from one Earth radius to 4 Earth radii, the gravitational force acting on the spaceship becomes approximately A) 1/16 as great B) 1/4 as great C) 16 times greater D) 4 times greater Determine the speed of the whirling stopper. 16. Base your answer to the following question on the information below. A kilogram car travels at a constant speed of 12 meters per second around a circular curve of radius 30. meters. What is the magnitude of the centripetal acceleration of the car as it goes around the curve? A) 0.40 m/s 2 B) 4.8 m/s 2 C) 800 m/s 2 D) 9,600 m/s A ball attached to a string is whirled at a constant speed of 2.0 meters per second in a horizontal circle of radius 0.50 meter. What is the magnitude of the ball's centripetal acceleration? A) 1.0 m/s 2 B) 2.0 m/s 2 C) 8.0 m/s 2 D) 4.0 m/s What is the centripetal acceleration of a ball traveling at 6.0 meters per second in a circle whose radius is 9.0 meters? A) 0.66 m/s 2 B) 1.5 m/s 2 C) 15 m/s 2 D) 4.0 m/s 2

3 19. Base your answer to the following question on the information and diagram below. 22. The diagram below shows a 5.0-kilogram bucket of water being swung in a horizontal circle of-meter radius at a constant speed of 2.0 meters per second. The diagram shows the top view of a -kilogram student at point A on an amusement park ride. The ride spins the student in a horizontal circle of radius meters, at a constant speed of meters per second. The floor is lowered and the student remains against the wall without falling to the floor. Which vector best represents the direction of the centripetal acceleration of the student at point A. A) B) C) D) 20. The magnitude of the centripetal force acting on an object traveling in a horizontal, circular path will decrease if the A) radius of the path is increased B) mass of the object is increased C) direction of motion of the object is reversed D) speed of the object is increased 21. An unbalanced force of 40. newtons keeps a 5.0-kilogram object traveling in a circle of radius 2.0 meters. What is the speed of the object? A) 8.0 m/s B) 2.0 m/s C) 16 m/s D) 4.0 m/s The magnitude of the centripetal force on the bucket of water is approximately A) 5.7 N B) 14 N C) 29 N D) 200 N 23. A ball of mass M at the end of a string is swinging 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 B) doubling V and halving R C) halving V and doubling R D) halving V and halving R

4 24. Base your answer to the following question 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. 25. Base your answer to the following question on the diagram below which shows a 2.0-kilogram cart traveling at a constant speed in a horizontal circle of radius 3.0 meters. The magnitude of the centripetal force of the cart is 24 Newtons. What minimum friction force must exist between the tires and the road to prevent the car from skidding as it rounds the curve? A) N B) N C) N D) N What is the speed of the cart? A) 6.0 m/s B) 16 m/s C) 36 m/s D) 4.0 m/s 26. A motorcycle of mass 100 kilograms travels around a flat, circular track of radius 10 meters with a constant speed of 20 meters per second. What force is required to keep the motorcycle moving in a circular path at this speed A) 200 N B) 400 N C) 2000 N D) 4000 N 27. A motorcycle travels around a flat circular track. If the speed of the motorcycle is increased, the force required to keep it in the same circular path A) decreases B) increases C) remains the same

5 Answer Key cons mom prac test 1. A 2. C m/s 4. C 5. C 6. B 7. A 8. D 9. A 10. C 11. C 12. B 13. A 14. A m/s 16. B 17. C 18. D 19. A 20. A 21. D 22. C 23. B 24. D 25. A 26. D 27. B