Test Bank Of Conceptual Physics 12th Edition 12E by Paul G. Hewitt

Test Bank Of Conceptual Physics 12th Edition 12E by Paul G. Hewitt

Conceptual Physics, 12e (Hewitt)
Chapter 7 Energy

7.1 Multiple-Choice Questions

1) The work done in pushing a TV set a distance of 2 m with an average force of 20 N is
A) 2 J.
B) 10 J.
C) 20 J.
D) 40 J.
E) 800 J.
Answer: D
Diff: 1
Topic: Work

2) The work you do when pushing a shopping cart twice as far while applying the same force is
A) half as much.
B) twice as much.
C) four times as much.
D) the same amount.
Answer: B
Diff: 1
Topic: Work

3) The work you do when pushing a shopping cart twice as far while applying twice the force is
A) half as much.
B) twice as much.
C) four times as much.
D) the same amount.
Answer: C
Diff: 1
Topic: Work

4) The work you do when pushing a shopping cart a given distance while applying twice as much force is
A) half as much.
B) twice as much.
C) four times as much.
D) the same amount.
Answer: B
Diff: 1
Topic: Work

5) No work is done by gravity on a bowling ball that rolls along a bowling alley because
A) no force acts on the ball.
B) little distance is covered by the ball.
C) the force on the ball is at right angles to the ball’s motion.
D) the ball’s speed remains constant.
Answer: C
Diff: 1
Topic: Work
6) A 1000-kg car and a 2000-kg car are hoisted to the same height. Raising the more massive car requires
A) less work.
B) as much work.
C) twice as much work.
D) four times as much work.
E) more than four times as much work.
Answer: C
Diff: 1
Topic: Work

7) The unit kilowatt-hour is a unit of
A) energy.
B) momentum.
C) power.
D) time.
Answer: A
Diff: 1
Topic: Work

8) One kilowatt-hour represents
A) 1 N.
B) 60 N/s.
C) 60,000 W.
D) 3.6 million joules.
E) none of these
Answer: D
Diff: 2
Topic: Work

9) Which task requires more work?
A) lifting the 50-kg sack 2 meters
B) lifting the 25-kg sack 4 meters
C) both require the same
D) need more information
Answer: C
Diff: 2
Topic: Work

10) The amount of work done on a heavy box carried by Nellie across a room at a constant speed
A) depends on the weight of the box.
B) depends on the distance walked.
C) depends on both weight of the box and distance walked.
D) is none.
E) none of the above
Answer: D
Diff: 2
Topic: Work
11) If you do work on a skateboard loaded with friends in one-third the usual time, you expend
A) one third as much power.
B) the usual power.
C) three times the usual power.
D) need more information.
Answer: C
Diff: 2
Topic: Work

12) The power expended doing 100 J of work in 50 s is
A) 1/2 W.
B) 2 W.
C) 4 W.
D) 50 W.
E) 5,000 W.
Answer: B
Diff: 2
Topic: Work

13) The power required to exert 4-N force over 3 meters in 2 seconds is
A) 4 W.
B) 6 W.
C) 8 W.
D) 12 W.
E) none of the above
Answer: B
Diff: 2
Topic: Work

14) Both a 50-kg sack is lifted 2 meters from the ground and a 25-kg sack is lifted 4 meters in the same time. The power expended in raising the 50-kg sack is
A) twice as much as the 25-kg sack.
B) half as much as the 25-kg sack.
C) the same.
D) need more information
Answer: C
Diff: 2
Topic: Work

15) A toy elevator is raised from the ground floor to the second floor in 20 seconds. The power needed using 1000 J of work, is
A) 20 W.
B) 50 W.
C) 100 W.
D) 1000 W.
E) 20,000 W.
Answer: B
Diff: 2
Topic: Work
16) The center of a long uniform log is raised to shoulder level while the other end is on the ground. If instead, the end of the log is raised to shoulder level, the work required is
A) half.
B) the same.
C) twice.
Answer: A
Diff: 3
Topic: Work

17) An object has gravitational potential energy due to its
A) speed.
B) acceleration.
C) momentum.
D) location.
E) none of the above
Answer: D
Diff: 1
Topic: Potential Energy

18) Relative to an initial height, an object raised twice as high has a gravitational potential energy
A) half as much
B) twice as much.
C) four times as much.
D) need more information
Answer: B
Diff: 1
Topic: Potential Energy

19) A crate of grapes lifted 10 meters gains 200 J of potential energy. If the same crate is instead lifted 20 meters, its gain in potential energy is
A) half as much.
B) the same.
C) twice as much.
D) four times as much.
E) more than four times as much.
Answer: C
Diff: 1
Topic: Potential Energy

20) When a drawn bow of potential energy 40 J is fired, the arrow will ideally have a kinetic energy
A) less than 40 J.
B) more than 40 J.
C) of 40 J.
Answer: C
Diff: 1
Topic: Potential Energy
21) A clerk can lift cylindrical packages 1 meter vertically, or can roll them up a 2-meter-long ramp to the same elevation. With the ramp, the applied force required is about
A) half as much.
B) the same.
C) twice as much.
D) four times as much.
Answer: A
Diff: 2
Topic: Potential Energy

22) A 2-kg ball is held 4 m above the ground. Relative to the ground its potential energy is
A) 6 J.
B) 8 J.
C) 32 J.
D) 80 J.
E) more than 80 J.
Answer: D
Diff: 2
Topic: Potential Energy

23) A 2-kg box of taffy candy has 40 J of potential energy relative to the ground. Its height above the ground is
A) 1 m.
B) 2 m.
C) 3 m.
D) 4 m.
E) none of the above
Answer: B
Diff: 2
Topic: Potential Energy

24) The ram of a pile driver drops onto the top of an iron beam, driving it partway into the ground. The distance that the beam sinks into the ground depends on the
A) initial height of the ram.
B) initial potential energy of the ram.
C) kinetic energy of the ram when it first hits the beam.
D) all of the above
Answer: D
Diff: 2
Topic: Potential Energy

25) An object that has kinetic energy must be
A) moving.
B) falling.
C) at an elevated position.
D) at rest.
E) none of the above
Answer: A
Diff: 1
Topic: Kinetic Energy

26) Two identical golf carts move at different speeds. The faster cart has twice the speed and therefore has
A) twice the kinetic energy.
B) four times the kinetic energy.
C) eight times the kinetic energy.
D) none of the above
Answer: B
Diff: 2
Topic: Kinetic Energy

27) A feather and a coin dropped in a vacuum fall with equal
A) forces due to gravity.
B) accelerations.
C) kinetic energies.
D) none of these
Answer: B
Diff: 2
Topic: Kinetic Energy

28) A melon is tossed straight upward with 100 J of kinetic energy. If air resistance is negligible the melon will return to its initial level with a kinetic energy of
A) less than 100 J.
B) more than 100 J.
C) 100 J.
D) need more information
Answer: C
Diff: 2
Topic: Kinetic Energy

29) A melon is projected into the air with 100 J of kinetic energy in the presence of air resistance. When it returns to its initial level its kinetic energy is
A) less than 100 J.
B) more than 100 J.
C) 100 J.
D) need more information
Answer: A
Diff: 2
Topic: Kinetic Energy

30) Danny Diver weighs 500 N and steps off a diving board 10 m above the water. Danny hits the water with kinetic energy of
A) 10 J.
B) 500 J.
C) 510 J.
D) 5000 J.
E) more than 5000 J.
Answer: D
Diff: 2
Topic: Kinetic Energy
31) Which has greater kinetic energy?
A) a car traveling at 30 km/hr
B) a car of half the mass traveling at 60 km/hr
C) both the same
D) need more information
Answer: B
Diff: 3
Topic: Kinetic Energy

32) Neglecting air resistance, Sammy Smarts on a high ladder releases a ball that strikes the ground with 100 J of kinetic energy. If he were to instead throw the ball straight upward, it will soon reach the ground with a kinetic energy of
A) less than 100 J.
B) 100 J.
C) more than 100 J.
Answer: B
Diff: 3
Topic: Kinetic Energy

33) If a Ping-Pong ball and a golf ball both move in the same direction with the same amount of kinetic energy, the speed of the Ping-Pong ball must be
A) less than the golf ball.
B) more than the golf ball.
C) both the same
D) need more information
Answer: B
Diff: 3
Topic: Kinetic Energy

34) Two identical particles move toward each other, one twice as fast as the other. Just before they collide, one has a kinetic energy of 25 J and the other 50 J. At this instant their total kinetic energy is
A) 25 J.
B) 50 J.
C) 75 J.
D) none of the above
E) need more information
Answer: C
Diff: 3
Topic: Kinetic Energy

35) When Joshua brakes his speeding bicycle to a stop, kinetic energy is transformed to
A) potential energy.
B) energy of motion.
C) energy of rest.
D) heat.
Answer: D
Diff: 1
Topic: Work-Energy Theorem
36) A bicycle that travels twice as fast as another when braking to a stop will skid
A) twice as far.
B) four times as far.
C) eight times as far
D) sixteen times as far.
E) depends on the bike’s mass
Answer: B
Diff: 2
Topic: Work-Energy Theorem

37) A bicycle that travels four as fast as another when braking to a stop will skid
A) twice as far.
B) four times as far.
C) eight times as far
D) sixteen times as far.
E) depends on the mass of the bike
Answer: D
Diff: 2
Topic: Work-Energy Theorem

38) A motorcycle moving at 50 km/h skids 10 m with locked brakes. How far will it skid with locked brakes when traveling at 150 km/h?
A) 10 m
B) 30 m
C) 50 m
D) 90 m
Answer: D
Diff: 2
Topic: Work-Energy Theorem

39) A cannonball has more kinetic energy than the recoiling cannon from which it is fired because the force on the ball
A) is more concentrated.
B) meets less resistance than the cannon on the ground.
C) acts over a longer distance.
Answer: C
Diff: 2
Topic: Work-Energy Theorem

40) About 40 J is required to push a crate 4 m across a floor. If the push is in the same direction as the motion of the crate, the force on the crate is about
A) 4 N.
B) 10 N.
C) 40 N.
D) 160 N.
Answer: B
Diff: 2
Topic: Work-Energy Theorem
41) If the speed of a bicycle is reduced to half before skidding to a stop, it will skid
A) one-eighth as far.
B) one-fourth as far.
C) one-half as far.
D) none of the above
Answer: B
Diff: 3
Topic: Work-Energy Theorem

42) Which requires the most amount of work by the brakes of a car?
A) slowing down from 100 km/h to 70 km/h
B) slowing down from 70 km/h to a stop
C) equal amounts for both
Answer: A
Diff: 3
Topic: Work-Energy Theorem

43) A 2500-N pile-driver ram falls 10 m and drives a post 0.1 m into the ground. The average impact force on the ram is
A) 2,500 N.
B) 25,000 N.
C) 250,000 N.
D) 2,500,000 N.
Answer: C
Diff: 3
Topic: Work-Energy Theorem

44) Two identical arrows, one with twice the kinetic energy of the other, are fired into a bale of hay. Compared with penetration of the slow arrow, the faster arrow penetrates
A) the same distance.
B) twice as far.
C) four times as far.
D) more than four times as far.
E) none of the above
Answer: B
Diff: 3
Topic: Work-Energy Theorem

45) Two identical arrows, one with twice the speed of the other, are fired into a bale of hay. Compared with penetration of the slow arrow, the faster arrow penetrates
A) the same distance.
B) two times as far.
C) four times as far.
D) more than four times as far.
E) none of the above
Answer: C
Diff: 3
Topic: Work-Energy Theorem
46) A ball rolling down an incline has its maximum potential energy at
A) the top.
B) a quarter of the way down.
C) halfway down.
D) the bottom.
Answer: A
Diff: 1
Topic: Conservation of Energy