Question 1

An ideal spring stretches by 21.0 cm when a 135-N object is hung from it.If instead you hang a fish from this spring,what is the weight of a fish that would stretch the spring by

Accepted Answer

A)  199 N
B)  91 N
C)  145 N
D)  279 N

Question 2

How much work would a child do while pulling a 12-kg wagon a distance of 
With a 
Force?

Accepted Answer

A)  95 J
B)  52 J
C)  67 J
D)  109 J

Question 3

It requires 0.30 kJ of work to fully drive a stake into the ground.If the average resistive force on the stake by the ground is 
How long is the stake?

Accepted Answer

A)  0.36 m
B)  0.23 m
C)  0.31 m
D)  0.41 m

Question 4

The kinetic friction force that a horizontal surface exerts on a 60.0-kg object is 50.0 N.If the initial speed of the object is 25.0 m/s,what distance will it slide before coming to a stop?

Accepted Answer

A)  15.0 m
B)  30.0 m
C)  375 m
D)  750 m

Question 5

Two cyclists who weigh the same and have identical bicycles ride up the same mountain,both starting at the same time.Joe rides straight up the mountain,and Bob rides up the longer road that has a lower grade.Joe gets to the top before Bob.Ignoring friction and wind resistance,which one of the following statements is true?

Accepted Answer

A)  The amount of work done by Joe is equal to the amount of work done by Bob,but the average power exerted by Joe is greater than that of Bob.
B)  The amount of work done by Joe is greater than the amount of work done by Bob,and the average power exerted by Joe is greater than that of Bob.
C)  Bob and Joe exerted the same amount of work,and the average power of each cyclist was also the same.
D)  The average power exerted by Bob and Joe was the same,but Joe exerted more work in getting there.

Question 6

Jill does twice as much work as Jack does and in half the time.Jill's power output is

Accepted Answer

A)  the same as Jack's power output.
B)  one-fourth as much as Jack's power output.
C)  one-half as much as Jack's power output.
D)  twice Jack's power output.
E)  four times Jack's power output.

Question 7

Three cars (car F,car G,and car H) are moving with the same speed and slam on their brakes.The most massive car is car F,and the least massive is car H.If the tires of all three cars have identical coefficients of kinetic friction with the road surface,which car travels the longest distance to skid to a stop?

Accepted Answer

A)  They all travel the same distance in stopping.
B)  car F
C)  car G
D)  car H

Question 8

A stone with a mass of 1.0 kg is tied to the end of a light string which keeps it moving in a circle with a constant speed of 4.0 m/s on a perfectly smooth horizontal tabletop.The radius of the path is 0.60 m.How much work does the tension in the string do on the stone as it makes one-half of a complete circle?

Accepted Answer

A)  100 J
B)  3.8 J
C)  0 J
D)  40 J
E)  80 J

Question 9

A stone is moving on a rough level surface.It has 24 J of kinetic energy,and the friction force on it is a constant 0.50 N.What is the maximum distance it can slide?

Accepted Answer

A)  2.0 m
B)  12 m
C)  24 m
D)  48 m

Question 10

A person carries a 2.00-N pebble through the path shown in the figure,starting at point A and ending at point B.The total time from A to B is 6.75 min.How much work did gravity do on the rock between A and B?

Accepted Answer

A)  30.0 J
B)  -30.0 J
C)  -56.0 J
D)  56.0 J
E)  -36.0 J

Question 11

A 1000-kg car is moving at 15 km/h.If a 2000-kg truck has 23 times the kinetic energy of the car,how fast is the truck moving?

Accepted Answer

A)  51 km/h
B)  72 km/h
C)  61 km/h
D)  41 km/h

Question 12

Two objects,one of mass m and the other of mass 2m,are dropped from the top of a building.If there is no air resistance,when they hit the ground

Accepted Answer

A)  both will have the same kinetic energy.
B)  the heavier one will have twice the kinetic energy of the lighter one.
C)  the heavier one will have four times the kinetic energy of the lighter one.
D)  the heavier one will have half the kinetic energy of the lighter one.
E)  the heavier one will have one-fourth the kinetic energy of the lighter one.

Question 13

If the force on an object is in the negative direction,the work it does on the object must be

Accepted Answer

A)  negative.
B)  positive.
C)  The work could be either positive or negative,depending on the direction the object moves.

Question 14

Person X pushes twice as hard against a stationary brick wall as person Y.Which one of the following statements is correct?

Accepted Answer

A)  Both do positive work,but person X does four times the work of person Y.
B)  Both do positive work,but person X does twice the work of person Y.
C)  Both do the same amount of positive work.
D)  Both do zero work.
E)  Both do positive work,but person X does one-half the work of person Y.

Question 15

A 1.0-kg object moving in a certain direction has a kinetic energy of 2.0 J.It hits a wall and comes back with half its original speed.What is the kinetic energy of this object at this point?

Accepted Answer

A)  2.0 J
B)  1.0 J
C)  0.50 J
D)  0.25 J
E)  4.0 J

Exam 7: Work and Kinetic Energy

A 1000-kg car is moving at 15 km/h.If a 2000-kg truck has 23 times the kinetic energy of the car,how fast is the truck moving?

Correct Answer
verified

An ideal spring stretches by 21.0 cm when a 135-N object is hung from it.If instead you hang a fish from this spring,what is the weight of a fish that would stretch the spring by

Correct Answer
verified

If the force on an object is in the negative direction,the work it does on the object must be

Correct Answer
verified

It requires 0.30 kJ of work to fully drive a stake into the ground.If the average resistive force on the stake by the ground is How long is the stake?

Correct Answer
verified

How much work would a child do while pulling a 12-kg wagon a distance of With a Force?

Correct Answer
verified

The kinetic friction force that a horizontal surface exerts on a 60.0-kg object is 50.0 N.If the initial speed of the object is 25.0 m/s,what distance will it slide before coming to a stop?

Correct Answer
verified

A 1.0-kg object moving in a certain direction has a kinetic energy of 2.0 J.It hits a wall and comes back with half its original speed.What is the kinetic energy of this object at this point?

Correct Answer
verified

Jill does twice as much work as Jack does and in half the time.Jill's power output is

Correct Answer
verified

Correct Answer
verified

Person X pushes twice as hard against a stationary brick wall as person Y.Which one of the following statements is correct?

Correct Answer
verified

A stone is moving on a rough level surface.It has 24 J of kinetic energy,and the friction force on it is a constant 0.50 N.What is the maximum distance it can slide?

Correct Answer
verified

A person carries a 2.00-N pebble through the path shown in the figure,starting at point A and ending at point B.The total time from A to B is 6.75 min.How much work did gravity do on the rock between A and B?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Two objects,one of mass m and the other of mass 2m,are dropped from the top of a building.If there is no air resistance,when they hit the ground

Correct Answer
verified

Exam 7: Work and Kinetic Energy

A 1000-kg car is moving at 15 km/h.If a 2000-kg truck has 23 times the kinetic energy of the car,how fast is the truck moving?

Correct AnswerverifiedShow Answer

An ideal spring stretches by 21.0 cm when a 135-N object is hung from it.If instead you hang a fish from this spring,what is the weight of a fish that would stretch the spring by

Correct AnswerverifiedShow Answer

If the force on an object is in the negative direction,the work it does on the object must be

Correct AnswerverifiedShow Answer

It requires 0.30 kJ of work to fully drive a stake into the ground.If the average resistive force on the stake by the ground is How long is the stake?

Correct AnswerverifiedShow Answer

How much work would a child do while pulling a 12-kg wagon a distance of With a Force?

Correct AnswerverifiedShow Answer

The kinetic friction force that a horizontal surface exerts on a 60.0-kg object is 50.0 N.If the initial speed of the object is 25.0 m/s,what distance will it slide before coming to a stop?

Correct AnswerverifiedShow Answer

A 1.0-kg object moving in a certain direction has a kinetic energy of 2.0 J.It hits a wall and comes back with half its original speed.What is the kinetic energy of this object at this point?

Correct AnswerverifiedShow Answer

Jill does twice as much work as Jack does and in half the time.Jill's power output is

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Person X pushes twice as hard against a stationary brick wall as person Y.Which one of the following statements is correct?

Correct AnswerverifiedShow Answer

A stone is moving on a rough level surface.It has 24 J of kinetic energy,and the friction force on it is a constant 0.50 N.What is the maximum distance it can slide?

Correct AnswerverifiedShow Answer

A person carries a 2.00-N pebble through the path shown in the figure,starting at point A and ending at point B.The total time from A to B is 6.75 min.How much work did gravity do on the rock between A and B?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Two objects,one of mass m and the other of mass 2m,are dropped from the top of a building.If there is no air resistance,when they hit the ground

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified