PHYSICS

74) You thoughtfully set a 1 kg box on top of a loaf of bread and the loaf compresses by 15 cm. Thinking of the bread as a spring, its spring constant is

A) 1 N/m B) 0.653 N/m C) 65.3 N/m D) 0.015 N/m

80) A ball hits a wall going 10 m/s, and bounces off going 7 m/s. The coefficient of restitution is

A) 1.41 B) 0.70 C) 0.49 D) -17 m/s

84) You are swinging a tin can around your head in a perfectly horizontal circle of radius 4 m. (This is really not possible but we're saying it almost happens.) If the speed of the can is 4 m/s what is its acceleration?

A) 1/4 m/s2 B) 4 m/s2 C) 16 m/s2 D) 4 m/s

18) The force of friction on a sliding object is 10 newtons. The applied force needed to maintain a constant velocity is A

A) 10 N. B) more than 10 N. C) less than 10 N.

28) If a freely falling object were somehow equipped with a speedometer on a planet where the acceleration due to gravity is 20 m/s/s, then its speed reading would increase each second by B

A) 10 m/s.B) 20 m/s. C) 30 m/s.D) 40 m/s.E) depends on its initial speed

59) A machine puts out 100 Watts of power for every 1000 Watts put into it. The efficiency of the machine is

A) 10%. B) 50%. C) 90%. D) 110%. E) none of these

79) The coefficient of restitution for a particular ball is 0.45. If he ball hits a surface traveling at 100 m/s its rebound speed will be

A) 100 m/s B) 90 m/s C) 45 m/s D) 45 m/s2

77) A popular playground toy is a flexible seat that has automobile springs attached to it for a little bounce. When a 200 N child sits on the toy, it compresses 5 mm downward. What is the ride's spring constant?

A) 1000 N B) 5 mm C) 40000 N/m D) 1000 N/m

24) A vehicle that weighs 4000 N on the surface of the Earth is travelling in outer space at a speed of 200 m/s. The smallest constant force that must be applied to stop it in 20 seconds is E

A) 20 N.B) 40 N. C) 400 N.D) more than 4000 N. E) 4000 N.

13) An object covers a distance of 8 meters in the first second of travel, another 8 meters during the next second, and 8 meters again during the third second. Its acceleration in meters per second per second is approximately D

A) 24. B) 5. C) 8. D) 0.

17) If a car accelerates from rest at 2 meters per second per second, its speed 3 seconds later will be about D

A) 3 m/s. B) 4 m/s. C) 2 m/s. D) 6 m/s.

48) A girl pulls on a 10-kg wagon with a constant horizontal force of 30 N. If there are no other horizontal forces, what is the wagon's acceleration in meters per second per second? A

A) 3.0 B) 0.3 C) 10 D) 30 E) 300

27) An object at rest near the surface of a distant planet starts to fall freely. If the acceleration there is twice that of the Earth, its speed one second later would be C

A) 30 m/s. B) 10 m/s. C) 20 m/s. D) 40 m/s.

31) A 500-N parachutist opens his chute and experiences an air resistance force of 800 N. The net force on the parachutist is B

A) 300 N downward.B) 300 N upward. C) 500 N downward. D) 800 N downward. E) 500 N upward.

42) A 300-kg bear grasping a vertical tree slides down at constant velocity. The friction force between the tree and the bear is A

A) 3000 N. B) 30 N.C) 300 N. D) more than 3000 N.

52) A bow is drawn so that it has 40 J of potential energy. When fired, the arrow will ideally have a kinetic energy that is

A) 40 J. B) less than 40 J. C) more than 40 J. D) impossible to predict without additional information

26) A horse gallops a distance of 10 kilometers in a time of 30 minutes. Its average speed is C

A) 40 km/h. B) 30 km/h. C) 20 km/h. D) 15 km/h.

55) A 2-kg mass is held 4 m above the ground. What is the approximate potential energy of the mass with respect to the ground?

A) 80 J B) 32 J C) 8 J D) 6 J E) none of these

82) You go through a loop in a roller coaster at constant speed. Where is your apparent weight a minimum?

A) At the top B) At the bottom C) Halfway up, going down D) Halfway up, going up

73) Imagine that you are on a fishing trip. Your friend gets a bite that exerts a force of about 100N on the pole and it bends by a certain amount. You have an identical pole, you get a hit that bends the pole about twice as much. You can estimate that the force on your pole is about

A) Can't tell B) 100 N C) 200 N D) 500 N

85) Your apparent weight is equal to your weight

A) In an elevator accelerating upwards. B) In an elevator accelerating downwards. C) In an elevator in free fall. D) In an elevator not accelerating.

60) A woman carries a heavy box across a room at a constant speed. How much work does she do on the box while walking? x.

A) More information is needed about the weight, distance, and her speed. B) none C) More information is needed about the speed and the distance. D) More information is needed about the distance walked. E) More information is needed about the weight of the bo

61) A flower pot of mass m falls from rest to the ground below, a distance h. Which statement is correct?

A) The KE of the pot when it hits the ground is proportional to h. B) The speed of the pot when it hits the ground is proportional to h. C) The speed of the pot when it hits the ground depends on m. D) The KE of the pot when it hits the ground does not depend on m. E) None of these are correct.

76) Cars are designed so that their bodies buckle (permanently deform) when they are in an accident. How does the buckling make the car safer by not allowing it to recoil (bounce) so much?

A) The buckling stores energy. B) The buckling dissipates the energy of the crash. C) The buckling provides energy to the crashing objects. D) The buckling gives the car a high coefficient of restitution.

78) Why do elastic balls bounce so well?

A) They store energy through compression, like a spring. B) They permanently deform, storing energy. C) They are all filled with a special energy-absorbent liquid. D) They are always thrown well.

83) You are riding an amusement park ride where you are strapped to the inside of a giant metal wheel that is rotating quite rapidly. Your acceleration is

A) Zero B) Straight down C) Toward the center D) Straight up

12) When a rocket ship accelerating in outer space runs out of fuel, it B

A) accelerates for a short time, then slows down to a constant velocity. B) no longer accelerates. C) accelerates for a short time, slows down, and eventually stops.

75) Suppose you are standing on a bathroom scale when you are flying in a jet airplane. For a moment the scale reads more than your actual weight. During that moment, it's exerting an upward force on you that is greater than your weight and you are

A) accelerating upward. B) accelerating downward. C) not accelerating. D) accelerating sideways.

22) An object in mechanical equilibrium is an object D

A) at rest. B) moving with constant velocity. C) having no acceleration. D) all of these

19) A truck is moving at constant velocity. Inside the storage compartment, a rock is dropped from the midpoint of the ceiling and strikes the floor below. The rock hits the floor B

A) behind the midpoint of the ceiling.B) exactly below the midpoint of the ceiling. C) ahead of the midpoint of the ceiling.D) More information is needed to solve this problem. E) none of these

29) An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the C

A) combined weight of the arrow and bowstring.B) air resistance against the bow. C) arrow's push against the bowstring.D) grip of the archer's hand on the bow.E) friction of the ground against the archer's feet.

33) The newton is a unit of C

A) density. B) mass. C) force. D) inertia.

10) Disregarding air resistance, objects fall with constant D

A) distances each successive second. B) speed.C) velocity. D) acceleration.

40) A player hits a ball with a bat. The action force is the impact of the bat against the ball. The reaction to this force is the A

A) force that the ball exerts on the bat.B) weight of the ball.C) weight of the bat. D) air resistance on the ball.E) grip of the player's hand against the ball.

32) If an object falling freely were somehow equipped with an odometer to measure the distance it travels, then the amount of distance it travels each succeeding second would be A

A) greater than the second before. B) doubled.C) constant. D) less and less each second.

51) If you push for a half hour or a whole hour against a stationary wall

A) half as much work is done during the half hour. B) no work on the wall is done in either case. C) twice as much work is done during the half hour. D) it is impossible to determine how much work is done.

34) The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity is C

A) less than 10 N. B) more than 10 N. C) 10 N.

36) Whereas Aristotle relied on logic in explaining nature, Galileo relied on D

A) mathematics. B) logic also. C) patterns. D) experiment.

23) A baseball player bats a ball with a force of 1000 N. The reaction force that the ball exerts against the bat is B

A) more than 1000 N. B) 1000 N.C) less than 1000 N. D) impossible to determine.

45) A package falls off a truck that is moving at 30 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is D

A) more than 30 m/s.B) less than 30 m/s but larger than zero. C) zero.D) about 30 m/s.E) More information is needed for an estimate.

39) As a ball falls, the action force is the pull of Earth on the ball. The reaction force is the A

A) pull of the ball's mass on the Earth. B) air resistance acting against the ball.C) acceleration of the ball. D) none of these

41) An object is propelled along a straight-line path in space by a force. If the mass of the object somehow becomes twice as much, its acceleration C

A) quadruples.B) stays the same. C) halves.D) doubles.E) none of these

81) When a baseball player hits a ball, the bat can respond by

A) rebounding. B) rotating. C) vibrating. D) any combination of (A), (B) or (C).

11) If your automobile runs out of fuel while you are driving, the engine stops but you do not come to an abrupt stop. The concept that most explains why is C

A) resistance. B) acceleration. C) inertia. D) gravity.

38) The force exerted on the tires of a car to directly accelerate it along a road is exerted by the A

A) road.B) tires.C) engine. D) air.E) none of these

35) A Mack truck and a Volkswagen traveling at the same speed have a head-on collision. The vehicle that undergoes the greatest change in velocity will be the B

A) same for both. B) Volkswagen. C) Mack truck.

50) Two factors that greatly affect air resistance on falling objects are the

A) size and mass of the object.B) size and weight of the object.C) size and speed of the object.

44) A kilogram is a measure of an object's D

A) size. B) weight. C) force. D) mass.

57) What task requires the most work; lifting a 50-kg sack 2 meters or lifting a 25-kg sack 4 meters?

A) the 25-kg sack B) the 50-kg sack C) Both require the same amount of work. D) impossible to determine without knowing the contents of the sack

30) The attraction of a person's body toward Earth is called weight. The reaction to this force is C

A) the Earth's surface pushing against the person's body. B) the person's body pushing against Earth's surface. C) the person's body pulling on the Earth. D) none of these

25) A rocket becomes progressively easier to accelerate as it travels upward from the ground mainly because B

A) the applied force on the rocket increases as burning of fuel progresses. B) the mass of the rocket decreases as fuel is burned. C) gravity becomes weaker with increased distance.

47) Earth pulls on the moon. Similarly the moon pulls on Earth, evidence that D

A) the moon is smaller so its pull is smaller.B) Earth is larger so its pull is larger.C) larger objects pull harder. D) these two pulls comprise an action-reaction pair.

20) Galileo's interpretation of motion differed from Aristotle's in that Galileo emphasized B

A) the role of distance in describing motion.B) time rates.C) the acceleration of free fall. D) all of these E) none of these

16) A automobile and a baby carriage traveling at the same speed collide head-on. The impact force is A

A) the same for both. B) greater on the automobile. C) greater on the baby carriage.

37) A car traveling at 100 km/hr strikes an unfortunate bug and splatters it. The force of impact is A

A) the same for both. B) greater on the car. C) greater on the bug.

43) Compared to the mass of a certain object on Earth, the mass of the same object on the moon is A

A) the same. B) one sixth as much.C) zero. D) six times as much.

53) A 1000-kg car and a 2000-kg car are hoisted the same distance. Raising the more massive car requires

A) twice as much work. B) four times as much work. C) less work. D) more than four times as much work. E) as much work.

46) A skydiver falls towards the Earth. The attraction of the Earth on the diver pulls the diver down. What is the reaction to this force? E

A) water resistance that will soon act upward on the diverB) the attraction to the planets, stars, and every particle in the universe C) air resistance the diver encounters while falling D) all of theseE) none of these

14) A 10-kg brick and a 1-kg book are dropped in a vacuum. The force of gravity on the 10-kg brick is B

A) zero. B) 10 times as much.C) one-tenth as much. D) the same as the force on the 1-kg book.

2) A person is attracted toward the center of Earth by a 500-N gravitational force. The Earth is attracted toward the person with a force of C

A) zero. B) 250 N. C) 500 N. D) 1000 N.

49) When a falling object has reached its terminal velocity, its acceleration isA

A) zero. B) g. C) constant.

21) A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at constant velocity is A

A) zero.B) equal to the product of its mass times its weight. C) equal to its weight divided by its mass. D) equal to its weight.

1) An apple weighs 1 N. When held at rest above your head, the net force on the apple is A

A)/ 0 N. B) 1 N. C) 0.1 N. D) 9.8 N. E) none of these

58) A car moves 4 times as fast as another identical car. Compared to the slower car, the faster car has

A)12 times the KE. B)8 times the KE. C)16 times the KE. D)4 times the KE.

9) At one instant a heavy object in air is moving upward at 50 meters per second. One second later its speed is approximately A

A)40 m/s. B) 55 m/s. C) 50 m/s. D) per second. One second later its speed is approximately

15) A skydiver of mass 100 kg experiences air resistance of 500 N, and an acceleration of A

A)about 0.5 g. B) about 0.4 g. C) about 0.3 g. D) about 0.2 g. E) more than 0.5 g.

4) The mass of a pet turtle that weighs 10 N is B

A)about 1000 kg. B)about 1 kg. C)about 10 kg. D) about 100 kg. E) none of these

5) If an object moves with constant acceleration, its velocity mustD

A)change by varying amounts depending on its speed. B)be constant also. C)always decrease. D) change by the same amount each second.

56) A job is done slowly, while an identical job is done quickly. Both jobs require the same amount of work, but different amounts of

A)energy. B)power. C) effort. D) none of these

3) A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that B

A)gravity tends to hold the milk carton secure. B) the milk carton has inertia. C) there is an action-reaction pair of forces. D) the milk carton has no acceleration. E) none of these

6) For an action force, there must be a reaction force that B

A)is slightly smaller in magnitude than the action force. B)is exactly equal in magnitude. C)is slightly larger in amplitude than the action force. D)always acts in the same direction.

8) A rock weighs 30 N on Earth. A second rock weighs 30 N on the moon. Which of the two rocks has the greater mass? A

A)the one on the moon B) the one on Earth C) They have the same mass. D) not enough information to say

54) A ball rolling down an incline has its maximum kinetic energy at

A)the top. B)three-quarters of the way down. C) the bottom. D) halfway down.

7) While a car travels around a circular track at a constant speed, its D

A)velocity is zero. B) inertia is zero. C) acceleration is zero. D) none of the above

64) A torque acting on an object tends to produce

A. a center of gravity. B. rotation. C. equilibrium. D. linear motion. E. velocity.

68) When a twirling ice skater brings her arms inward, her rotational speed

A. decreases. B. remains the same. C. increases.

66) Toss a baseball bat into the air and it rotates about its

A. heavier end. B. center of mass. C. geometrical center.

67) On a balanced seesaw, a boy three times as heavy as his partner sits

A. more than 1/3 the distance from the pivot point. B. 1/3 the distance from the pivot point. C. less than 1/3 the distance from the pivot point.

70) A spinning Frisbee is thrown between two persons in a park. The motion of the Frisbee is tional.

A. purely rotational. B. purely translational. C. rotational and translational. D. neither rotational nor transla

69) A swimming pool in a rotating space habitat is located in a 1/4g region. If a diver can jump 1 m high in a 1g region, how high can the same diver jump in the swimming area?

A.2 m B.16 m C. more than 16 m D. 4 m E. 1 m

71) Suppose the time it takes for a wind turbine to rotate triples. By what factor will its rotational kinetic energy change?

A.It will double. B.It will quadruple. C. It will decrease to 1/9 its original value. D. It will increase to 9 times its original value.

72) What type of friction causes bearings to not waste much energy?

A.Sliding B.Static C.Both D. Neither

63) Which moves faster in m/s on a merry-go-round: a horse on the inside or a horse on the outside near the outer rail?

A.inside horse B.outside horse C. Both move at the same speed in m/s.

62) Your pet hamster sits on a record player whose angular speed is constant. If he moves to a point twice as far from the center, then his linear speed

A.remains the same. B.halves. C.doubles.

65) Put a pipe over the end of a wrench when trying to turn a stubborn nut on a bolt, to effectively make the wrench handle twice as long, you'll multiply the torque by

A.two. B.eight. C.four.

A glance at your speedometer will tell you your b

a. average speed. b./ instantaneous speed. c. overall speed. d. acceleration.