Semester one Physics

Transcription

1 Class: Date: Semester one Physics Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The table shows the results of an experiment with a projectile fired from a spring gun. The results could be most easily interpreted if the data were a. entered into a spreadsheet. c. plotted in a histogram. b. put into a database. d. plotted as range vs. angle. 2. To create real-time graphs of an object s displacement versus time and velocity versus time, a student would need to use a a. motion sensor. c. potential difference probe. b. low-g accelerometer. d. force probe. 3. A student does an experiment to measure the acceleration of a falling object, which is 9.8 m/s^2. The student obtains an experimental value of 14.6 m/s^2. The reason for this variation is most likely due to a. human error. c. local fluctuations in gravity. b. air resistance. d. the mass of the object. 1

2 4. The picture shows two objects that were dropped and recorded with a stroboscopic camera. The best explanation for the results is that object A a. has less air resistance. c. has a greater mass. b. was dropped from a greater height. d. accelerated more slowly. 5. A student applied a constant force to a toy truck. A graph of the truck s movement is shown. Which of the following could best explain the change in velocity at time X? a. The truck s momentum became greater than its inertia. b. The truck went from moving in a straight path to moving in a curved path. c. The truck began traveling up a slightly sloped surface. d. The truck went from rolling on a rough surface to rolling on a polished surface. 6. A student wires a series circuit that includes a block of rubber and a light bulb. She states that she does not expect the light bulb to light up when current is applied to the circuit. Which of the following best describes her statement? a. It is a conclusion based on observed data c. It is a procedure based on her hypothesis about electrical phenomena. b. It is a hypothesis based on knowledge of the theory of electrical phenomena. about electrical phenomena. d. It is a theory based on her observations of electrical phenomena. 2

3 7. A student attempts to measure the mass of a brick by measuring the force required to accelerate it to 1 m/s^2 on a level surface. The force required is 2 N, and the student concludes that the brick has a mass of 2 kg. A balance shows that the mass of the brick is really 1.5 kg. The experimental error is most likely due to a. gravity. c. friction. b. work. d. inertia. 8. The graph was presented to a science class. An accurate analysis of the data in the graph could be used to support a hypothesis that the United States has a. become increasingly dependent on c. regulated production by prohibiting imported petroleum. b. become more efficient in the conservation of petroleum companies from producing petroleum d. increased its reserves while consuming imported petroleum. 9. How much time will it take for a person to walk the length of football field (100 yards) at a constant speed of 5 ft/s? a. 20 seconds c. 60 seconds b. 33 seconds d. 166 seconds 10. A ball is dropped from rest from a height 6.0 meters above the ground. The ball falls freely and reaches the ground 1.12 seconds later. What is the average speed of the ball a. 5.5 m/s c. 6.6 m/s b. 6.1 m/s d. 11 m/s 3

4 11. An object moves away from a motion detector with constant speed. Which graph best represents the motion of the object? a. A c. C b. B d. D 12. A 10-newton force and a 15-newton force are acting from a single point in opposite directions. What additional force must be added to produce equilibrium? a. 5 N acting in the same direction as the 10-N force c. 10 N acting in the same direction as the 10-N force b. 5 N acting in the same direction as the 15-N force d. 25 N acting in the same direction as the 15-N force 13. A student holds a book at rest in an outstretched hand. The force exerted on the book by the student is equal to the book s a. mass c. volume b. weight d. density 4

5 14. The graph below shows the velocity of a car that is moving in a straight line. During which of the following intervals are forces on the car balanced? a. q to r c. s to t b. r to s d. t to u 15. The figure shows a block that is being pulled along the floor. According to the figure, what is the acceleration of the block? a. 2/m/s^2 c. 4 m/s^2 b. 3 m/s^2 d. 6 m/s^2 16. A 60-kg child on a skateboard experiences a 75-N force as shown. What is the expected acceleration of the child? a m/2^2 c m/s^2 b m/s^2 d m/s^2 17. A soccer player kicks a 0.5-kilogram stationary ball with a force of 50 newtons. What is the force on the player s foot? a. 0 N c. 50 N b. 25 N d. 100 N 5

6 18. A student in a lab experiment jumps upward off a common bathroom scale as the lab partner records the scale reading. What does the lab partner observe during the instant the student pushes off? a. The scale reading will remain unchanged during the entire time the student is in contact with the scale. c. The scale reading will increase during the entire time the student is in contact with the scale. b. The scale reading will increased momentarily then will decrease as the student is moving upward from the scale. d. The scale reading will decrease momentarily then will increase as the student is moving upward from the scale. 19. What event will produce the greatest increase in the gravitational force between the two masses? a. doubling the large mass c. reducing the small mass by half b. doubling the distance between the masses d. reducing the distance between the masses by half 20. Objects on the surface of Earth experience a large downward force although the universal gravitational constant is very small. Which of the following best explains this phenomenon? a. Objects on Earth s surface exert a gravitational pull as strong as Earth s, regardless of the gravitational constant. c. Earth s mass is large enough that it gravity remains strong even when multiplied by a small constant. b. The universal gravitational constant only describes relationships between small objects in outer space. d. The universal gravitational constant increases in proportion with the mass of an object. 21. A communication satellite is in a circular orbit around Earth. If the speed of the satellite is constant, the force acting on the satellite a. is zero. c. points toward the center of Earth at all times. b. is decreasing. d. points in the direction that the satellite is moving. 22. A satellite that is moving in a circular orbit around Earth and maintaining a constant speed will experience a a. changing gravitational force toward c. changing acceleration away from Earth. Earth. b. net gravitational force toward Earth. d. net acceleration way from Earth. 6

7 23. The picture shows the circular path of a toy plane being swung around on a string. What path would the toy take if the string broke? a. A c. C b. B d. D 7

8 24. A ball on a rope swings around a vertical pole. In which direction will the ball fly if released at the location shown? a. W c. Y b. X d. Z 25. A small car is being driven in a circular path at a constant speed on a horizontal surface. What is the direction of the frictional force that keeps the car from skidding as it travels along this path? a. opposite the direction of the velocity of c. toward the center of the circle the car b. in the same direction as the velocity of the car d. outward from the center for the circle 26. A 2.0-kilogram mass is moving with a speed of 3.0 m/s. What is the kinetic energy of the mass? a. 1.5 J c. 9.0 J b. 6.0 J d J 27. Three objects move with a velocity of 1 m/s. What is the total kinetic energy of the system? a. 1 J c. 5 J b. 2 J d. 10 J 28. What is the kinetic energy of an object with a mass of 10 kilograms traveling at a speed of 10 meters per second? Assume no other forces act upon the object. a. 100 joules c joules b. 500 joules d. 50, 000 joules 29. What is the kinetic energy of 2-kg toy car moving at a velocity of 5 m/s? a. 5 J c. 25 J b. 10 J d. 50 J 8

9 30. A 50-kilogram firefighter is on a ladder 10 meters above the ground. When the firefighter descends to 5 meters above the ground, the firefighter s gravitational potential energy will decrease by a joules c. 490 joules b joules d joules 31. A hydraulic lift used at an automotive repair shop raises a 1000-kilogram car two meters off of the ground. What is the potential energy given to the car? a J c J b J d. 19,600 J 32. A 5-kilogram mass is lifted from the ground to a height of 10 meters. The gravitational potential energy of the mass is increased by approximately a. 0.5 J c. 250 J b. 50 J d. 500 J 33. A high diver steps off a diving platform that is 10 meters above the water. If no air resistance is present during the fall there will be decrease in the diver s a. gravitational potential energy. c. kinetic energy. b. total mechanical energy. d. momentum. 34. A 2.5-kg brick falls to the ground from a 3-m-high roof. What is the approximate kinetic energy of the brick just before it touches the ground? a. 75 J c. 12 J b. 38 J d. 11 J 35. Starting from rest, a 2-kilogram block of wood slides a distance of two meters down a frictionless slope as shown. What is the approximate kinetic energy of the block at the end of the ramp? a. 20 J c. 200 J b. 40 J d. 400 J 36. A child is on a sled moving down a hill at 20 meters/second. The combined mass of the sled and child is 100 kilograms. The momentum of the child and sled is a. 5 kilogram x m/s. c kilogram x m/s b. 20 kilogram x m/s. d kilogram x m/s 37. A 70-kg skier leaves a ski jump at a velocity of 14 m/s. What is the skier s momentum at that instant? a. 5 N x S c. 980 N x s b. 50 N x s d N x s 38. What is the momentum of an asteroid that has a mass of 1.35 x 10^12 kg and a velocity of 2.55 x 10 ^4 m/s? a x 10^-8 kg m/s c x 10 ^16 kg m/s b x 10 ^7 kg m/s d x 10^20 kg m/s 9

10 39. When is linear momentum conserved? a. when only nonlinear forces are present c. when internal forces exceed external forces b. when more linear than nonlinear forces are in the system d. when the net force on the system is zero 40. In collisions between two objects, kinetic energy is conserved only a. if one of the objects was initially at rest. c. in inelastic collisions. b. if potential energy converts to work energy. d. in elastic collisions. 41. A temporary force acting on a 2-kg object traveling at a velocity of 5 m/s causes the object to slow to a velocity of 2 m/s. What was the decrease in momentum of the object? a. 4 kg m/s c. 6 kg m/s b. 5 kg m/s d. 7 kg m/s 42. When these two freight cars of different mass collide and couple, what will be their resultant velocity? a. 1 m/s c. 4 m/s b. 2 m/s d. 8 m/s 43. The diagram depicts a 2-kg mass colliding with and sticking to a second box. What is the mass of the second block? a. 4 kg c. 8 kg b. 6 kg d. 9 kg 10

11 44. In an elastic collision, momentum is conserved, as is a. kinetic energy. c. speed. b. potential energy. d. velocity. 45. Newton had the insight to see that the. a. moon is moving b. moon orbits Earth c. force on the moon has the same nature as the force on an apple d. moon always keeps one side toward Earth e. none of the above 46. Newton hypothesized that the moon. a. is a projectile b. is falling around Earth c. has tangential velocity that prevents it from falling into Earth d. is actually attracted to Earth e. all of the above 47. Newton reasoned that the gravitational attraction between Earth and the moon must be. a. reduced by distance b. independent of distance c. directly proportional to distance d. the same at all distances e. all of the above 48. If Earth's mass decreased to one half its original mass, with no change in radius, then your weight would. a. stay the same b. decrease to one half your original weight c. decrease to one quarter your original weight d. none of the above 49. Two objects move toward each other because of gravitational attraction. As the objects get closer and closer, the force between them. a. remains constant b. decreases c. increases 50. Suppose the gravitational force between two massive spheres is 100 N. If the distance between the spheres is doubled, what is the force between the masses? a. 400 N b. 200 N c. 100 N d. 50 N e. 25 N 51. If you stood atop a ladder on Earth that was as tall as Earth's radius (so you were twice as far from Earth's center) your weight atop the ladder would be. a. one-eighth its normal value b. one-quarter its normal value c. half its normal value d. none of the above 11

12 52. In physics, work is defined as a. force times time. b. force divided by distance. c. distance divided by time. d. force divided by time. e. force times distance. 53. If you lift two loads up one story, how much work do you do compared to lifting just one load up one story? a. One quarter as much b. One half as much c. The same amount d. Twice as much e. Four times as much 54. The unit of work is the a. watt. b. meter. c. joule. d. newton. e. second. 55. The unit of power is the a. newton. b. meter. c. joule. d. second. e. watt. 56. Potential energy is the energy an object has because of its a. density. b. size. c. location. d. speed. e. temperature. 57. Kinetic energy of an object is equal to a. its mass multiplied by its acceleration squared. b. one half the product of its mass times its speed squared. c. its mass multiplied by its speed. d. one half the product of its mass times its speed. e. its mass multiplied by its acceleration. 58. An arrow in a bow has 70 J of potential energy. Assuming no loss of energy to heat, how much kinetic energy will it have after it has been shot? a. 0 J b. 35 J c. 50 J d. 70 J e. 140 J 59. Energy is changed from one form to another with no net loss or gain. a. Sometimes true b. Always false c. Always true 12

13 60. As a pendulum swings back and forth a. at the end points of its swing, its energy is all potential. b. at the lowest part of its swing, its energy is all kinetic. c. kinetic energy is transformed into potential energy. d. potential energy is transformed into kinetic energy. e. all of the above 61. When a car s speed triples, its kinetic energy a. remains the same. b. triples. c. increases by four times. d. increases by nine times. e. none of the above 62. A job is done slowly, and an identical job is done quickly. Both jobs require the same amount of work but different amounts of a. energy. b. power. c. both A and B d. none of the above 63. Which has greater angular speed, a horse near the outside rail of a merry-go-round or a horse near the inside rail? a. Neither they both have the same angular speed. b. The inside horse c. The outside horse 64. Which of the following is NOT a unit of rotational speed? a. Meters per second b. Revolutions per minute c. Revolutions per second d. Rotations per second e. Rotations per minute 65. A tin can whirled on the end of a string moves in a circle because a. the can continually pulls on the string. b. once the can starts moving, that is its natural tendency. c. there is a force on the can pulling it outward. d. there is an inward force acting on the can. e. all of the above 66. If you whirl a tin can on the end of a string and the string suddenly breaks, the can will a. fly directly away from you. b. fly off, tangent to its circular path. c. fly directly toward you. d. spiral in toward your hand. e. spiral away from your hand. 67. Speed is a. a measure of how fast something is moving. b. always measured in terms of a unit of distance divided by a unit of time. c. the distance covered per unit time. d. all of the above. e. none of the above. 13

14 68. When you look at the speedometer in a moving car, you can see the car's a. average distance traveled. b. instantaneous acceleration. c. average speed. d. instantaneous speed. e. average acceleration. 69. Acceleration is defined as the CHANGE in a. time it takes to move from one place to another place. b. velocity of an object. c. distance divided by the time interval. d. velocity divided by the time interval. e. time it takes to move from one speed to another speed. 70. A car starts from rest and after 7 seconds it is moving at 42 m/s. What is the car s average acceleration? a m/s 2 b m/s 2 c. 6 m/s 2 d. 7 m/s 2 e. none of the above 71. In the absence of air resistance, objects fall at constant a. speed. b. velocity. c. acceleration. d. distances each successive second. e. all of the above 72. Suppose you take a trip that covers 180 km and takes 3 hours to make. Your average speed is a. 30 km/h. b. 60 km/h. c. 180 km/h. d. 360 km/h. e. 540 km/h. 73. A ball is thrown straight up. At the top of its path its instantaneous speed is a. 0 m/s. b. about 5 m/s. c. about 10 m/s. d. about 20 m/s. e. about 50 m/s. 74. A ball is thrown straight up. At the top of its path its acceleration is a. 0 m/s 2. b. about 5 m/s 2. c. about 10 m/s 2. d. about 20 m/s 2. e. about 50 m/s 2. 14

15 75. When something falls to the ground, it accelerates. This acceleration is called the acceleration due to gravity and is symbolized by the letter g. What is the value of g on Earth's surface? a. 0 m/s 2 b. about 5 m/s 2 c. about 10 m/s 2 d. about 20 m/s 2 e. about 50 m/s If a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by a. about 5 m/s. b. about 10 m/s. c. about 15 m/s. d. a variable amount. e. a rate that depends on its initial speed. 77. Whenever an object exerts a force on another object, the second object exerts a force of the same magnitude, but in the opposite direction to that of the first object. a. Sometimes true b. Always true c. Always false 78. A high school student hits a nail with a hammer. During the collision, there is a force a. on the nail but not on the hammer. b. on the nail and also on the hammer. c. on the hammer but not on the nail. 79. Forces always occur a. as single quantities. b. by themselves. c. in pairs. d. in triplets. 80. A player hits a ball with a bat. The action force is the impact of the bat against the ball. What is the reaction to this force? a. The force of the ball against the bat b. The weight of the ball c. Air resistance on the ball d. The grip of the player's hand against the bat e. none of the above 81. A rocket is able to accelerate in the vacuum of space when it fires its engines. The force that propels the rocket is the force a. of the rocket on the exhaust gases. b. of the exhaust gases on the rocket. c. neither A nor B 82. Two people pull on a rope in a tug-of-war. Each pulls with 400 N of force. What is the tension in the rope? a. 0 N b. 400 N c. 600 N d. 800 N e. none of the above 15

16 83. Which one of the following steps is NOT a part of the scientific method? a. Perform experiments to test the predictions. b. Repeat the experiments until the answers match the predictions. c. Formulate a general rule based on the predictions and experimental outcome. d. Make a guess about the answer to a problem and predict its consequences. e. Recognize a problem. 84. A hypothesis is a. the long side of a right triangle. b. an educated guess that has yet to be proven by experiment. c. close agreement by competent observers of observations of the same phenomena. d. a guess that has been tested over and over again and always found to be true. e. a synthesis of a large collection of information that includes guesses. 85. A theory is a. an educated guess that has yet to be proven by experiment. b. a synthesis of a large collection of information including well-tested guesses. c. close agreement by competent observers of observations of the same phenomena. d. a guess that has been tested over and over again and always found to be true. e. a science story about atoms and molecules. 16

17 Semester one Physics Answer Section MULTIPLE CHOICE 1. ANS: D PTS: 1 STA: 1 a 2. ANS: A PTS: 1 STA: 1 a 3. ANS: A PTS: 1 STA: 1 b 4. ANS: A PTS: 1 STA: 1 c 5. ANS: C PTS: 1 STA: 1 d 6. ANS: B PTS: 1 STA: 1 f 7. ANS: C PTS: 1 STA: 1 J 8. ANS: A PTS: 1 STA: 1 m 9. ANS: C PTS: 1 STA: 1 a 10. ANS: A PTS: 1 STA: 1 a 11. ANS: B PTS: 1 STA: 1 a 12. ANS: A PTS: 1 STA: 1 b 13. ANS: B PTS: 1 STA: 1 b 14. ANS: B PTS: 1 STA: 1 b 15. ANS: A PTS: 1 STA: 1 c 16. ANS: B PTS: 1 STA: 1 c 17. ANS: C PTS: 1 STA: 1 d 18. ANS: B PTS: 1 STA: 1 d 19. ANS: D PTS: 1 STA: 1 e 20. ANS: C PTS: 1 STA: 1 e 21. ANS: C PTS: 1 STA: 1 f 22. ANS: B PTS: 1 STA: 1 f 23. ANS: A PTS: 1 STA: 1 g 24. ANS: B PTS: 1 STA: 1 g 25. ANS: C PTS: 1 STA: 1 g 26. ANS: C PTS: 1 STA: 2 a 27. ANS: C PTS: 1 STA: 2 a 28. ANS: B PTS: 1 STA: 2 a 29. ANS: C PTS: 1 STA: 2 a 30. ANS: D PTS: 1 STA: 2 b 31. ANS: D PTS: 1 STA: 2 b 32. ANS: D PTS: 1 STA: 2 b 33. ANS: A PTS: 1 STA: 2 c 34. ANS: A PTS: 1 STA: 2 c 35. ANS: A PTS: 1 STA: 2 c 36. ANS: D PTS: 1 STA: 2 d 37. ANS: C PTS: 1 STA: 2 d 38. ANS: C PTS: 1 STA: 2 d 39. ANS: D PTS: 1 STA: 2 e 1

18 40. ANS: D PTS: 1 STA: 2 e 41. ANS: C PTS: 1 STA: 2 f 42. ANS: A PTS: 1 STA: 2 g 43. ANS: A PTS: 1 STA: 2 g 44. ANS: A PTS: 1 STA: 2 g 45. ANS: C PTS: 1 DIF: 2 REF: p. 168 p. 169 OBJ: 12.1 STA: Ph.1.m 46. ANS: E PTS: 1 DIF: 2 REF: p. 169 OBJ: 12.2 STA: Ph.1.m 47. ANS: A PTS: 1 DIF: 2 REF: p. 169 OBJ: 12.2 STA: Ph.1.m 48. ANS: B PTS: 1 DIF: 2 REF: p. 173 OBJ: 12.4 STA: Ph.1.e Ph.1.m 49. ANS: C PTS: 1 DIF: 3 REF: p. 172 OBJ: 12.4 STA: Ph.1.e Ph.1.m 50. ANS: E PTS: 1 DIF: 3 REF: p. 175 OBJ: 12.5 STA: Ph.1.e Ph.1.m 51. ANS: B PTS: 1 DIF: 3 REF: p. 175 p. 176 OBJ: 12.5 STA: Ph.1.e Ph.1.m 52. ANS: E PTS: 1 DIF: 1 REF: p. 103 OBJ: 8.1 STA: Ph.3.a 53. ANS: D PTS: 1 DIF: 2 REF: p. 103 p. 104 OBJ: 8.1 STA: Ph.3.a 54. ANS: C PTS: 1 DIF: 1 REF: p. 104 OBJ: 8.1 STA: Ph.3.a 55. ANS: E PTS: 1 DIF: 1 REF: p. 105 OBJ: ANS: C PTS: 1 DIF: 1 REF: p. 106 OBJ: 8.4 STA: Ph.2.b 57. ANS: B PTS: 1 DIF: 1 REF: p. 108 OBJ: 8.5 STA: Ph.2.a 58. ANS: D PTS: 1 DIF: 2 REF: p. 109 p. 110 OBJ: 8.6 STA: Ph.2.c 59. ANS: C PTS: 1 DIF: 1 REF: p. 109 OBJ: 8.6 STA: Ph.2.c 60. ANS: E PTS: 1 DIF: 2 REF: p. 110 OBJ: 8.6 STA: Ph.2.c 61. ANS: D PTS: 1 DIF: 3 REF: p. 108 OBJ: 8.5 STA: Ph.2.a 62. ANS: B PTS: 1 DIF: 2 REF: p. 104 p. 105 OBJ: ANS: A PTS: 1 DIF: 2 REF: p. 123 p. 124 OBJ: 9.2 STA: Ph.1.l 64. ANS: A PTS: 1 DIF: 1 REF: p. 123 p. 124 OBJ: 9.2 STA: Ph.1.l 2

19 65. ANS: D PTS: 1 DIF: 2 REF: p. 127 p. 128 OBJ: 9.4 STA: Ph.1.l 66. ANS: B PTS: 1 DIF: 3 REF: p. 127 OBJ: 9.4 STA: Ph.1.l 67. ANS: D PTS: 1 DIF: 2 REF: p. 11 p. 12 OBJ: 2.2 STA: Ph.1.a Ph.1.b 68. ANS: D PTS: 1 DIF: 1 REF: p. 12 OBJ: 2.2 STA: Ph.1.a Ph.1.b 69. ANS: D PTS: 1 DIF: 1 REF: p. 15 OBJ: 2.4 STA: Ph.1.c 70. ANS: C PTS: 1 DIF: 2 REF: p. 16 OBJ: 2.4 STA: Ph.1.c 71. ANS: C PTS: 1 DIF: 2 REF: p. 17 p. 18 p. 19 OBJ: 2.5 STA: Ph.1.b Ph.1.c Ph.2.c 72. ANS: B PTS: 1 DIF: 2 REF: p. 13 OBJ: 2.2 STA: Ph.1.a Ph.1.b 73. ANS: A PTS: 1 DIF: 2 REF: p. 18 p. 19 OBJ: 2.5 STA: Ph.1.b Ph.1.c Ph.2.c 74. ANS: C PTS: 1 DIF: 3 REF: p. 18 OBJ: 2.5 STA: Ph.1.b Ph.1.c Ph.2.c 75. ANS: C PTS: 1 DIF: 1 REF: p. 17 OBJ: 2.5 STA: Ph.1.b Ph.1.c Ph.2.c 76. ANS: B PTS: 1 DIF: 1 REF: p. 18 OBJ: 2.5 STA: Ph.1.b Ph.1.c Ph.2.c 77. ANS: B PTS: 1 DIF: 1 REF: p. 75 OBJ: 6.2 STA: Ph.1.d 78. ANS: B PTS: 1 DIF: 2 REF: p. 76 OBJ: 6.3 STA: Ph.1.d 79. ANS: C PTS: 1 DIF: 1 REF: p. 75 OBJ: 6.2 STA: Ph.1.d 80. ANS: A PTS: 1 DIF: 2 REF: p. 76 OBJ: 6.3 STA: Ph.1.d 81. ANS: B PTS: 1 DIF: 2 REF: p. 76 OBJ: 6.3 STA: Ph.1.d 82. ANS: B PTS: 1 DIF: 3 REF: p. 79 OBJ: 6.5 STA: Ph.1.d 83. ANS: B PTS: 1 DIF: 2 REF: p. 2 OBJ: ANS: B PTS: 1 DIF: 1 REF: p. 2 OBJ: ANS: B PTS: 1 DIF: 1 REF: p. 3 OBJ: 1.4 3