Conceptual Physics Chapter 4 Review

21) A 10-N falling object encounters 4 N of air resistance. The net force on the object is A) 0 N. B) 4 N. C) 6 N. D) 10 N. E) none of these

A) 0 N.

22) A 10-N falling object encounters 10 N of air resistance. The net force on the object is A) 0 N. B) 4 N. C) 6 N. D) 10 N. E) none of these

A) 0 N.

23) An apple weighs 1 N. When held at rest above your head, the net force on the apple is A) 0 N. B) 0.1 N. C) 1 N. D) 9.8 N. E) none of these

A) 0 N.

77) A sack of potatoes weighing 200 N falls from an airplane. As the velocity of fall increases, air resistance also increases. When air resistance equals 200 N, the sack's acceleration in meters per second per second is A) 0. B) 4.9. C) 9.8. D) infinite. E) none of these

A) 0.

61) A 10-kilogram block is pushed across a horizontal surface with a horizontal force of 20 N against a friction force of 10 N. The acceleration of the block in meters per second per second is A) 1. B) 2. C) 5. D) 10. E) none of these

A) 1.

40) The mass of a pet turtle that weighs 10 N is A) about 1 kg. B) about 10 kg. C) about 100 kg. D) about 1000 kg. E) none of these

A) about 1 kg.

10) The newton is a unit of A) force. B) mass. C) density. D) inertia.

A) force.

75) A large and a small person wish to parachute at equal terminal velocities. The larger person will have to A) get a larger parachute. B) jump lightly. C) pull upward on the supporting strands to decrease the downward net force. D) jump first from the plane.

A) get a larger parachute.

78) A coconut and a feather fall from a tree through the air to the ground below. The amount of air-resistance force is A) greater on the coconut. B) greater on the feather. C) the same on each.

A) greater on the coconut.

29) A heavy block at rest is suspended by a vertical rope. When the block is accelerated upward by the rope, the rope tension A) increases. B) decreases. C) remains the same

A) increases.

6) If one object has twice as much mass as another object, it also has twice as much A) inertia. B) velocity. C) acceleration due to gravity. D) volume. E) all of these

A) inertia.

14) A force is a vector quantity because it has both A) magnitude and direction. B) Mass and acceleration. C) Action and reaction counterparts.

A) magnitude and direction.

11) In which case would you have the largest mass of gold? If your chunk of gold weighed 1 N on the A) moon. B) Earth. C) planet Jupiter.

A) moon.

74) A light woman and a heavy man jump from an airplane at the same time and open their same-size parachutes at the same time. Which person will get to a state of zero acceleration first? A) the light woman B) the heavy man C) Both should arrive at the same time. D) not enough information

A) the light woman

8) Strange as it may seem, it is just as hard to accelerate a car on a level surface on the moon as it is here on the Earth. This is because A) the mass of the car is independent of gravity. B) the weight of the car is independent of gravity. C) Nonsense! A car is much more easily accelerated on the moon than on the Earth.

A) the mass of the car is independent of gravity.

69) If more horizontal force is applied to a sliding object than is needed to maintain a constant velocity A) the object accelerates in the direction of the applied force. B) the object accelerates opposite the direction of the applied force. C) the friction force increases. D) two of the above E) none of the above

A) the object accelerates in the direction of the applied force.

41) The force required to maintain an object at a constant velocity in free space is equal to A) zero. B) the mass of the object. C) the weight of the object. D) the force required to stop it. E) none of these

A) zero.

47) A 10-N block and a 1-N block lie on a horizontal frictionless table. To provide them with equal horizontal acceleration, we would have to push with A) equal forces on each block. B) 10 times as much force on the heavier block. C) 10 squared or 100 times as much force on the heavier block. D) 1/10 as much force on the heavier block. E) none of these

B) 10 times as much force on the heavier block.

46) A push on a 1-kg brick accelerates it. Neglecting friction, to equally accelerate a 10-kg brick, one would have to push with A) just as much force. B) 10 times as much force. C) 100 times as much force. D) one-tenth the amount of force. E) none of these

B) 10 times as much force.

15) A 10-kg brick and a 1-kg book are dropped in a vacuum. The force of gravity on the 10-kg brick is A) the same as the force on the 1-kg book. B) 10 times as much. C) one-tenth as much. D) zero.

B) 10 times as much.

59) A car traveling at 22 m/s comes to an abrupt halt in 0.1 second when it hits a tree. What is the deceleration in meters per second per second of the car? A) 110 B) 220 C) 800 D) 880 E) can't be solved without the mass of the car

B) 220

9) A ride on a roller-coaster car containing 6 passengers takes 3 minutes. Neglecting friction, a similar ride with 12 passengers aboard would take A) 1.5 minutes. B) 3 minutes. C) 6 minutes. D) 18 minutes.

B) 3 minutes.

36) 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) 0.3 B) 3.0 C) 10 D) 30 E) 300

B) 3.0

43) A man weighing 800 N stands at rest on two bathroom scales so that his weight is distributed evenly over both scales. The reading on each scale is A) 200 N. B) 400 N. C) 800 N. D) 1600 N. E) none of these

B) 400 N.

19) An object is pulled northward by a force of 10 N and at the same time another force of 15 N pulls it southward. The magnitude of the resultant force on the object is A) 0 N. B) 5 N. C) 25 N. D) 150 N.

B) 5 N.

54) A 1-kg rock that weighs 9.8 N is thrown straight upward at 20 m/s. Neglecting air resistance, the net force that acts on it when it is half way to the top of its path is A) less than 9.8 N. B) 9.8 N. C) more than 9.8 N.

B) 9.8 N.

50) A rock is thrown vertically into the air. At the top of its path, its acceleration in meters per second per second is A) zero. B) 9.8. C) between 0 and 9.8. D) greater than 9.8.

B) 9.8.

62) If you are driving at 20 m/s and slam on your brakes and skid at 0.5 g to a full stop, the skidding time in seconds is A) about 3. B) about 4. C) about 5. D) about 6. E) more than 6.

B) about 4.

37) If the mass of an object does not change, a constant net force on the object produces constant A) velocity. B) acceleration. C) both of these D) neither of these

B) acceleration.

1) Which has the greater mass? A) a king-size pillow B) an automobile battery C) neither - both have the same

B) an automobile battery

28) Your car is coasting on level ground at 60 km/h and you apply the brakes until the car slows to 40 km/h. If you suddenly release the brakes now, the car tends to A) momentarily regain its higher initial speed. B) continue moving at 40 km/h. C) decrease in speed if no other forces act.

B) continue moving at 40 km/h.

80) A skydiver jumps from a high-flying plane. As her velocity of fall increases, her acceleration A) increases. B) decreases. C) remains unchanged regardless of air resistance

B) decreases.

42) An object following a straight-line path at constant speed A) has a net force acting upon it in the direction of motion. B) has zero acceleration. C) has no forces acting on it. D) none of these

B) has zero acceleration.

73) Two objects of the same size, but unequal weights are dropped from a tall tower. Taking air resistance into consideration, the object to hit the ground first will be the A) lighter object. B) heavier object. C) Both hit at the same time. D) not enough information

B) heavier object.

17) If an object's mass is decreasing while a constant force is applied to the object, the acceleration A) decreases. B) increases. C) remains the same.

B) increases.

26) Whenever the net force on an object is zero, its acceleration A) may be less than zero. B) is zero. C) may be more than zero

B) is zero.

27) The maximum acceleration of a car while towing a second car twice its mass, compared to its acceleration with no car in tow, is A) one half. B) one third. C) one fourth. D) the same. E) none of these

B) one third.

48) A rocket becomes progressively easier to accelerate as it travels upward from the ground mainly because A) gravity becomes weaker with increased distance. B) the applied force on the rocket increases as burning of fuel progresses. C) the mass of the rocket decreases as fuel is burned.

B) the applied force on the rocket increases as burning of fuel progresses.

5) Your weight is A) equal to your mass. B) the gravitational attraction force between you and the Earth. C) a property of mechanical equilibrium. D) all of these

B) the gravitational attraction force between you and the Earth.

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

B) the one on the moon

7) Compared to the mass of a certain object on Earth, the mass of the same object on the moon is A) one sixth as much. B) the same. C) six times as much. D) zero.

B) the same.

72) When a falling object has reached its terminal velocity, its acceleration is A) constant. B) zero. C) g.

B) zero.

24) An apple at rest weighs 1 N. The net force on the apple when it is in free fall is A) 0 N. B) 0.1 N. C) 1 N. D) 9.8 N. E) none of these

C) 1 N.

20) The force of friction on a sliding object is 10 newtons. The applied force needed to maintain a constant velocity is A) more than 10 N. B) less than 10 N. C) 10 N.

C) 10 N.

58) An object released from rest on another planet requires one second to fall a distance of 6 meters. What is the acceleration in meters per second per second due to gravity on this planet? A) 3 B) 6 C) 12 D) 15 E) none of these

C) 12

35) A tow truck exerts a force of 3000 N on a car, accelerating it at 2 meters per second per second. What is the mass of the car? A) 500 kg B) 1000 kg C) 1500 kg D) 3000 kg E) none of these

C) 1500 kg

53) A jumbo jet has a mass of 100,000 kg. The thrust for each of its four engines is 50,000 N. What is the jet's acceleration in meters per second per second when taking off? A) 0.25 B) 1 C) 2 D) 4 E) none of these

C) 2

64) A 2000-kg car experiences a braking force of 10,000 N and skids to a stop in 6 seconds. The speed of the car just before the brakes were applied was A) 1.2 m/s. B) 15 m/s. C) 30 m/s. D) 45 m/s. E) none of these

C) 30 m/s.

63) A 1000-kg automobile enters a freeway on-ramp at 20 m/s and accelerates uniformly up to 40 m/s in a time of 10 seconds. How far does the automobile travel during that time? A) 100 m B) 200 m C) 300 m D) 400 m E) none of these

C) 300 m

45) When a woman stands at rest with both feet on a scale, it reads 500 N. When she gently lifts one foot, the scale reads A) less than 500 N. B) more than 500 N. C) 500 N.

C) 500 N.

51) A block is dragged without acceleration in a straight-line path across a level surface by a force of 6 N. What is the force of friction between the block and the surface? A) less than 6 N B) more than 6 N C) 6 N D) need more information to say

C) 6 N

30) A 1-kg mass at the Earth's surface weighs A) 1 N. B) 4.9 N. C) 9.8 N. D) 10.8 N. E) none of these

C) 9.8 N.

39) A bag of groceries has a mass of 10 kilograms and a weight of A) about 1 N. B) about 10 N. C) about 100 N. D) about 1000 N. E) more than 1000 N.

C) about 100 N.

67) The human body can, under certain conditions, withstand an acceleration of 10 g. What net force would produce this acceleration of a 50-kg person? A) about 500 N B) about 2500 N C) about 5000 N D) about 25,000 N E) none of these

C) about 5000 N

68) If an object of constant mass experiences a constant net force, it will have a constant A) velocity. B) speed. C) acceleration. D) position. E) more than one of the above

C) acceleration.

33) Hang from a pair of gym rings and the upward support forces of the rings will always A) each be half your weight. B) each be equal to your weight. C) add up to equal your weight

C) add up to equal your weight

44) Neglecting friction, a large block of ice and a small block of ice start sliding down an incline together. The heavier block will get to the bottom A) before the light block. B) after the light block. C) at the same time as the light block

C) at the same time as the light block

52) Suppose a particle is being accelerated through space by a 10-N force. Suddenly the particle encounters a second force of 10 N in the opposite direction from the first force. The particle with both forces acting on it A) is brought to a rapid halt. B) decelerates gradually to a halt. C) continues at the speed it had when it encountered the second force. D) theoretically tends to accelerate toward the speed of light. E) none of these

C) continues at the speed it had when it encountered the second force.

49) A rock is thrown vertically into the air. At the very top of its trajectory the net force on it is A) less than its weight. B) more than its weight. C) equal to its weight.

C) equal to its weight.

31) If a non-rotating object has no acceleration, then we can say for certain that it is A) at rest. B) moving at constant non-zero velocity. C) in mechanical equilibrium. D) all of these E) none of these

C) in mechanical equilibrium.

2) A kilogram is a measure of an object's A) weight. B) force. C) mass. D) size.

C) mass.

13) An object's weight may properly be expressed in units of A) meters. B) kilograms. C) newtons. D) Cubic centimeters.

C) newtons.

71) 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.

C) size and speed of the object.

70) If less horizontal force is applied to a sliding object than is needed to maintain a constant velocity A) the object accelerates in the direction of the applied force. B) the friction force increases. C) the object eventually slides to a stop. D) none of the above

C) the object eventually slides to a stop.

38) A force of 1 N accelerates a mass of 1 kg at the rate of 1 m/s2. The acceleration of a mass of 2 kg acted upon by a net force of 2 N is A) half as much. B) twice as much. C) the same. D) none of these

C) the same.

16) An object is propelled along a straight-line path by a force. If the net force were doubled, the object's acceleration would be A) half as much. B) the same. C) twice as much. D) four times as much. E) none of these

C) twice as much.

34) A car has a mass of 1000 kg and accelerates at 2 meters per second per second. What is the magnitude of the net force exerted on the car? A) 500 N B) 1000 N C) 1500 N D) 2000 N E) none of these

D) 2000 N

66) What horizontally-applied force will accelerate a 400-kg crate at 1 m/s2 across a factory floor against a friction force half its weight? A) 600 N B) 1600 N C) 2000 N D) 2400 N E) none of these

D) 2400 N

82) A 500-N parachutist opens his chute and experiences an air resistance force of 800 N. The net force on the parachutist is A) 300 N downward. B) 500 N downward. C) 800 N downward. D) 300 N upward. E) 500 N upward.

D) 300 N upward.

60) A 10-kilogram block with an initial velocity of 10 m/s slides 10 meters across a horizontal surface and comes to rest. It takes the block 2 seconds to stop. The stopping force acting on the block is about A) 5 N. B) 10 N. C) 25 N. D) 50 N. E) none of these

D) 50 N.

76) A skydiver, who weighs 500 N, reaches terminal velocity of 90 km/h. The air resistance on the diver is then A) 90 N. B) 250 N. C) 410 N. D) 500 N. E) none of these

D) 500 N.

32) When you relax at rest with your left foot on one bathroom scale and your right foot on a similar scale, each of the scales will A) indicate exactly half your weight. B) indicate part of your total weight but not necessarily half of it. C) indicate different values that will equal your weight when added together. D) Any of the above may be correct.

D) Any of the above may be correct.

57) A skydiver of mass 100 kg experiences air resistance of 500 N, and an acceleration of A) about 0.2 g. B) about 0.3 g. C) about 0.4 g. D) about 0.5 g. E) more than 0.5 g.

D) about 0.5 g.

25) Which has zero acceleration? An object A) at rest. B) moving at constant velocity. C) in mechanical equilibrium. D) all of these E) none of these

D) all of these

3) Compared to a 1-kg block of solid iron, a 2-kg block of solid iron has twice as much A) inertia. B) mass. C) volume. D) all of these E) none of these

D) all of these

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

D) halves.

79) A lightweight feather slides off a table and falls through the air until it reaches the floor. During the time of its fall, its acceleration A) keeps increasing. B) keeps decreasing. C) never changes. D) is sometimes zero.

D) is sometimes zero.

81) A skydiver steps from a helicopter and falls for a few seconds until he reaches his terminal velocity. Thereafter, until he opens his parachute, his acceleration A) is constant. B) increases. C) decreases. D) is zero. E) none of these

D) is zero.

55) A 1-kg ball is thrown at 10 m/s straight upward. Neglecting air resistance, the net force that acts on the stone when it is halfway to the top of its path is about A) 1/2 N. B) 1 N. C) 5 N. D) 7.5 N. E) 10 N.

E) 10 N.

65) An astronaut on another planet drops a 1-kg rock from rest and finds that it falls a vertical distance of 2.5 meters in one second. On this planet, the rock has a weight of A) 1 N. B) 2 N. C) 3 N. D) 4 N. E) 5 N.

E) 5 N.

4) Compared to a 1-kg block of solid iron, a 2-kg block of solid iron has the same A) mass. B) volume. C) weight. D) all of these E) none of these

E) none of these

56) The brakes of a speeding truck are slammed on and it skids to a stop. If the truck were heavily loaded so that it had twice the total mass, the skidding distance would be A) 1/2 as far. B) 1 1/2 times as far. C) 2 times as far. D) 4 times as far. E) the same.

E) the same.