33. A jumper in the long-jump goes into the jump with a speed of 11 m/s at an angle of 20ø above the horizontal. How far does the jumper jump?

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1 31. A stone is thrown horizontally with an initial speed of 10 m/s from the edge of a cliff. A stop watch measures the stone's trajectory time from the top of the cliff to the bottom to be 4.3 s. What is the height of the cliff? a) 22 m b) 43 m c) 77 m d) 91 m 32. A jumper in the long-jump goes into the jump with a speed of 12 m/s at an angle of 20ø above the horizontal. How long is the jumper in the air before returning to the Earth? a) 0.21 s b) 0.42 s c) 0.84 s d) 1.3 s 33. A jumper in the long-jump goes into the jump with a speed of 11 m/s at an angle of 20ø above the horizontal. How far does the jumper jump? a) 7.8 m b) 7.9 m c) 8.0 m d) 8.1 m 34. A girl throws a rock horizontally, with a velocity of 10 m/s, from a bridge. It falls 20 m to the water below. How far does the rock travel horizontally before striking the water? a) 14 m b) 16 m c) 20 m d) 24 m 35. A ball is thrown at an original speed of 8.0 m/s at an angle of 35ø above the horizontal. What is the speed of the ball when it returns to the same horizontal level? a) 4.0 m/s b) 8.0 m/s c) 16 m/s d) 9.8 m/s 36. A projectile is launched with an initial velocity of 60.0 m/s at an angle of 30.0ø above the horizontal. How far does it travel? a) 152 m b) 160 m c) 184 m d) 318 m

2 37. A projectile is launched with an initial velocity of 60.0 m/s at an angle of 30.0ø above the horizontal. What is the maximum height reached by the projectile? a) 23 m b) 46 m c) 69 m d) 92 m 38. A package of supplies is dropped from a plane, and one second later a second package is dropped. Neglecting air resistance, the distance between the falling packages will a) be constant. b) decrease. c) increase. d) depend on their weight. 39. A plane flying horizontally at a speed of 50.0 m/s and at an elevation of 160 m drops a package. Two seconds later it drops a second package. How far apart will the two packages land on the ground? a) 100 m b) 162 m c) 177 m d) 283 m 40. At what angle should a water-gun be aimed in order for the water to land with the greatest horizontal range? a) 0ø b) 30ø c) 45ø d) 60ø 41. The acceleration of gravity on the moon is only one-sixth of that on earth. If you hit a baseball on the moon with the same effort (and at the speed and angle) that you would on earth, the ball would land a) the same distance away. b) one-sixth as far. c) 6 times as far. d) 36 times as far. 42. When a football in a field goal attempt reaches its maximum height, its speed is a) zero. b) less than its initial speed. c) equal to its initial speed. d) greater than its initial speed. 43. You are throwing a ball for the second time. If the ball leaves your hand with twice the velocity it had on your first throw, its horizontal range R (compared to your first serve) would be a) 1.4 times as much. b) half as much. c) twice as much. d) four times as much.

3 44. A pilot drops a bomb from a plane flying horizontally. When the bomb hits the ground, the horizontal location of the plane will a) be behind the bomb. b) be over the bomb. c) be in front of the bomb. d) depend on the speed of the plane when the bomb was released. 45. A ball is thrown with a velocity of 20 m/s at an angle of 60ø above the horizontal. What is the horizontal component of its instantaneous velocity at the exact top of its trajectory? a) 10 m/s b) 17 m/s c) 20 m/s d) zero 46. A ball is thrown with a velocity of 20 m/s at an angle of 60ø above the horizontal. What is the vertical component of its instantaneous velocity at the exact top of its trajectory? a) 10 m/s b) 17 m/s c) 20 m/s d) zero 47. A soccerball is kicked with a velocity of 25 m/s at an angle of 45ø above the horizontal. What is the vertical component of its acceleration as it travels along its trajectory? a) 9.80 m/s2 downward b) (9.80 m/s2) X sin (45ø) downward c) (9.80 m/s2) X sin (45ø) upward d) (9.80 m/s2) upward 48. A stone is thrown horizontally from the top of a tower at the same instant a ball is dropped vertically. Which object is traveling faster when it hits the level ground below? a) It is impossible to tell from the information given. b) The stone c) The ball d) Neither, since both are traveling at the same speed. 49. A ball thrown horizontally from a point 24 m above the ground, strikes the ground after traveling horizontally a distance of 18 m. With what speed was it thrown? a) 6.1 m/s b) 7.4 m/s c) 8.1 m/s d) 8.9 m/s

4 50. A rifle bullet is fired at an angle of 30ø below the horizontal with an initial velocity of 800 m/s from the top of a cliff 80 m high. How far from the base of the cliff does it strike the level ground below? a) 130 m b) 140 m c) 150 m d) 160 m 51. An Olympic athlete throws a javelin at four different angles above the horizontal, each with the same speed: 30ø 40ø 60ø 80ø. Which two throws cause the javelin to land the same distance away? a) 30ø and 80ø b) 40ø and 60ø c) 40ø and 80ø d) 30ø and 60ø 52. A bullet is fired horizontally, and at the same instant a second bullet is dropped from the same height. Ignore air resistance. Compare the times of fall of the two bullets. a) The fired bullet hits first. b) The dropped bullet hits first. c) They hit at the same time. d) Cannot tell without knowing the masses. 53. Ignoring air resistance, the horizontal component of a projectile's velocity a) is zero. b) remains constant. c) continuously increases. d) continuously decreases. 54. Ignoring air resistance, the horizontal component of a projectile's acceleration a) is zero. b) remains a non-zero constant. c) continuously increases. d) continuously decreases. 64. A fighter plane moving 200 m/s horizontally fires a projectile with speed 50.0 m/s in a forward direction 30.0ø below the horizontal. What is the speed of the projectile with respect to a stationary observer on the ground? a) 245 m/s b) 250 m/s c) 268 m/s d) 293 m/s ANSWER KEY FOR TEST - UNTITLED 31. d 37. b 43. d 49. c 55. a 32. c 38. c 44. b 50. b 56. c 33. b 39. a 45. a 51. d 57. a 34. c 40. c 46. d 52. c 58. b 35. b 41. c 47. a 53. b 59. b 36. d 42. b 48. b 54. a 60. c

5 61. a 63. b 65. c 67. a 69. b 62. d 64. a 66. a 68. b 70. d