13. By noticing that Uranus's strange orbit, two astronomers independently discovered Neptune by using the law of gravitation and A. knowing that Uranus has several moons. B. using exceptions to the law of gravitation. C. knowing the law of gravitation fails at large distances. D. a perturbation of an additional center of force. 14. When you carry a heavy load with one arm, how would you to change the center of gravity of your body and the load? A. change the mass of your body B. be ready to grab something in case you fall C. hold your free arm away from your body D. change the weight of your body and the load 15. How could you best describe the force that acts on clothes in a washing machine during the spin cycle? A. a circular movement towards a center B, a circular movement outward C. an acceleration upward D. an acceleration downward 16. The force exerted by a 2.4-m massless string on a 0.84-kg object being swung in a horizontal circle is 4.2 N. What is the tangential velocity of the object? A 3.5 m/s B. 6.0 m/'s C. 8.5 mis D. 12 m/'s 17. A bicyclist on a riverside path sees a boat coming toward her. Relative to the ground, the bicyclist is biking at 16 kmih west and the boat is traveling at 30 kmih east. How quickly does the bicyclist approach the boat? A. 46 km/h B. 30 km/h C. 16 kmh D. 14 km/h L30. What happens to the gravitational force between two objects if the distance between them is decreased by one-third? A. It will remain the same. B. The gravitational force is one-ninth as large. C. The gravitational force is 6 times as large. D. The gravitational force is 9 times as large. 31. A rock and a rubber ball have the same mass. If you drop them both from the top of a 3-story building, which object will produce a lesser impulse? A. The rock will produce a lesser impulse because it will dent the surface it hits. B. The rock will produce a lesser impulse because it will not bounce as high as the ball it hits the ground. C. The rubber ball will produce a lesser impulse because it will bounce higher. D. The rubber ball will produce a lesser impulse because it will stop when it hits the ground. 32. A ball is launched at 4.5 m/s at 66* above the horizontal. What is the maximum height of the ball? A. 0.17 m B. 0.21 m C. 0.86 m D. 1.05 m 33. Weight is the measure of the force of on an object. A. density B. mass C. gravity D. velocity 34. Two objects move toward each other because of attraction. As the objects get closer and closer, the force between them increases A. electrical B. gravitational C. accelerational D. magnetic 35. Angular momentum is defined as A, momentum times rotational velocity. B. mass times velocity. C. rotational inertia times Inear velocity. D. rotational inertia times rotational velocity.36. An example of static equilibrium is A. the downward motion of a thrown ball. B. the upward motion of a thrown ball. C. a ball rolling on the floor. D. a ball resting on the floor. 37. A bolt is to be tightened with a torque of 8.0 N-m. If you have a wrench that is 0.35 m long, what force is needed if it is applied to the wrench at a point perpendicular to the wrench? A. 28N B. 84 N C. 15.7 N D. 23 N 38. A 560 N woman stands on top of a very tall ladder so she is one Earth radius above Earth's surface. How much does she weigh? A. zero B. 140 N C. 280 N D. 560 N 39. A bicycle wheel with a radius of 36 crn is given an angular acceleration of 2.63 radis? by applying a force of 0.34 N on the edge of the wheel. What is the wheel's moment of inertia ? A. 0.02 kgom2 B. 0.03 kgem C. 0.05 kgem2 D. 5.00 kg-m? 40. M the planet Jupiter underwent gravitational collapse, its rate of rotation about its axis would A decrease. B. increase. C. stay the same. D. More information is needed. 41. Any object thrown into the air with a spin rotates about its A heaviest side B. midpoint. C. center of mass. D. endpoint42. Nellie Newton swings a rock into a circular path while holding an attached string overhead. The string makes a 45-degree angle to the vertical (comprising a "conical pendulum"). The centripetal force vectors involved will Include A. Nellie Newton's height. B. air resistance C. the tension in the string. D. the horizontal component of the string tension. 43. Since Earth is attracted to the sun, the Earth could fall into the sun if A. the tangential velocity would equal zero. B. It has sufficient tangential velocity. C. there is an equal force holding it away from the sun. D. it has an accelerating tangential velocity. 44. The train worker climbs the ladder with a speed of vit = 0.25 m/s, as the train moves forward at vig = 0.75 m/s. Find the direction of the worker relative to the ground? A. 18" above the horizontal B. 27' above the horizontal C. 45" above the horizontal D. 72" above the horizontal 45. A bicycle wheel with diameter 26 inches, rotates at a constant 452 rewmin, Is its angular acceleration A. zero B. constant C. positive D. negative A. 4 mis 46. A 6 kg ball is thrown with 24kg-mis of momenturn. What is the ball's velocity? B. 9.8 mis C. 10 mis D. 24 m/'s47. What happens to the gravitational force between two objects if one of the masses is tripled? A. It will also triple B. It will be cubed. C. It will be cut in thirds. O. It wil remain the same. 48. A satellite is in orbit at a distance of 7060 km from the center of Earth. The mass of Earth is 5.98 x 1024 kg. What is the orbital speed of the satellite? G Is the universal gravitation constant (6.67 x 10-11 N - m2/kg?). A. 5.65 x 107 mis B. 7 52 x 103 mis C. 2.38 x 105 mis D. 8.87 x 10 m/'s 48. Compared to the gravitational field well above the surface of Earth, the gravitational field at Earth's surface is A. larger. B. the same. C. smaller. D. dependent upon temperature. 50. Two metal spheres, each weighing 22.0 kg. are placed 0.05 m apart. Calculate the magnitude of the gravitational force the two spheres exert on each other. G is the universal gravitation constant (6.67 x 10-11 N . m2/kg?)- A. 2.93 x 10-# N B. 6.46 x 10-7 N C. 5.87 x 10 7 N D. 1.20 x 10-6N9. A butterfly is sitting on a merry-go-round 3.1 m from the center. If the tangential velocity of the ride is 0.78 m/s, what is the centripetal acceleration of the dragonfly? A. 0.18 m/s2 B. 0.20 mis C. 0.25 m/s2 D. 3.9 m/s2 10. A good explanation of why a ball would lose speed as it rolls down an incline involves A. the decrease of a force that acts on it. B. increasing the friction between it and the incline. C. the additional torque that acts on it. D. the concentrated rotational inertia of the ball. . 11, Compared to a sports car moving at 60 miles per hour, the same sports car moving at 30 miles per hour has A. twice as much momentum. B. one-hall as much momentum. C. the same momentum. D. momentum equaling its kinetic energy. 12. A bicycle wheel with diameter 26 inches, rotates at a constant 452 rewmin. Is the total acceleration of a point on the tire A. zero B. inward C. outward D. tangential