Physics Principles with Applications 7th Edition Giancoli By Test Bank

Physics Principles with Applications 7th Edition Giancoli By Test Bank

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

1) Person X pushes twice as hard against a stationary brick wall as person Y. Which one of the

1)

following statements is correct?

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

2) Two men, Joel and Jerry, push against a car that has stalled, trying unsuccessfully to get it moving. 2) Jerry stops after 10 min, while Joel is able to push for 5.0 min longer. Compare the work they do on

the car.

1. Joel does 25% more work than Jerry.
2. Joel does 50% more work than Jerry.
3. Jerry does 50% more work than Joel.
4. Joel does 75% more work than Jerry.
5. Neither of them does any work.

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

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3. The work could be either positive or negative, depending on the direction the object moves.

4)

A 35-N bucket of water is lifted vertically 3.0 m and then returned to its original position. How

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much work did gravity do on the bucket during this process?

A) 180 J

B)45J

C)0J

D)90J

E) 900 J

5)

You throw a baseball straight up. Compare the sign of the work done by gravity while the ball

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goes up with the sign of the work done by gravity while it goes down.

1. The work is negative on the way up and positive on the way down.
2. The work is negative on the way up and on the way down because gravity is always downward.
3. The work is positive on the way up and negative on the way down.
4. The work is positive on the way up and positive on the way down.

6) Which one has larger kinetic energy: a 500-kg object moving at 40 m/s or a 1000-kg object moving 6) at 20 m/s?

1. The 1000-kg object
2. The 500-kg object
3. Both have the same kinetic energy.

7) A truck has four times the mass of a car and is moving with twice the speed of the car. If K_t and K_c 7)

refer to the kinetic energies of truck and car respectively, it is correct to say that

A) K_t =

1

Kc.

B) K_t = 2K_c.

C) K_t = 16K_c.

D) K_t = K_c.

E) K_t = 4K_c.

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8) Three cars (car F, car G, and car H) are moving with the same speed and slam on their brakes. The

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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?

A) They all travel the same distance in stopping.

B) Car G

C) Car F

D) Car H

9) Three cars (car L, car M, and car N) are moving with the same speed and slam on their brakes. The

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most massive car is car L, and the least massive is car N. If the tires of all three cars have identical

coefficients of kinetic friction with the road surface, for which car is the amount of work done by

friction in stopping it the greatest?

A) The amount of work done by friction is the same for all cars.

B) Car N

C) Car M

D) Car L

10) A 4.0 kg object is moving with speed 2.0 m/s. A 1.0 kg object is moving with speed 4.0 m/s. Both

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objects encounter the same constant braking force, and are brought to rest. Which object travels

the greater distance before stopping?

A) the 1.0 kg object

B) the 4.0 kg object

C) Both objects travel the same distance.

D) It cannot be determined from the information given.

11) You slam on the brakes of your car in a panic, and skid a certain distance on a straight level road.

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If you had been traveling twice as fast, what distance would the car have skidded, under the same

conditions?

A) It would have skidded twice as far.

B) It would have skidded 1.4 times farther.

C) It would have skidded 4 times farther.

D) It would have skidded one half as far.

E) It is impossible to tell from the information given.

12) Which requires more work, increasing a car’s speed from 0 mph to 30 mph or from 50 mph to 60

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mph?

A) 50 mph to 60 mph

1. B) 0 mph to 30 mph
2. C) It is the same in both cases.

13) A stone is held at a height h above the ground. A second stone with four times the mass of the first 13) one is held at the same height. The gravitational potential energy of the second stone compared to

that of the first stone is

1. one-fourth as much.
2. four times as much.
3. twice as much.
4. one-half as much.

1. the same.

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14) You and your friend, who weighs the same as you, want to go to the top of the Eiffel Tower. Your

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friend takes the elevator straight up. You decide to walk up the spiral stairway, taking longer to do so. Compare the gravitational potential energy of you and your friend, after you both reach the top.

1. It is impossible to tell, since the times you both took are unknown.
2. Both of you have the same amount of gravitational potential energy at the top.
3. Your friend’s gravitational potential energy is greater than yours, because he got to the top faster.
4. It is impossible to tell, since the distances you both traveled are unknown.
5. Your gravitational potential energy is greater than that of your friend, because you traveled a greater distance in getting to the top.

15) The graphs shown show the magnitude F of the force exerted by a spring as a function of the

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distance x the spring has been stretched. For which one of the graphs does the spring obey Hooke’s law?

A) Graph a

B) Graph b

C) Graph c

D) Graph d

E) Graph e

16) A heavy dart and a light dart are launched horizontally on a frictionless table by identical ideal

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springs. Both springs were initially compressed by the same amount. Which of the following

statements about these darts are correct? (There could be more than one correct choice.)

1. The lighter dart leaves the spring moving faster than the heavy dart.
2. Both darts had the same initial elastic potential energy.
3. Both darts move free of the spring with the same speed.
4. The heavy dart had more initial elastic potential energy than the light dart.
5. The darts both have the same kinetic energy just as they move free of the spring.

17) When you throw a pebble straight up with initial speed V, it reaches a maximum height H with no 17) air resistance. At what speed should you throw it up vertically so it will go twice as high?

1. A) 2V B) 4V C) 16V D) 8V E) 2V

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18)

When you drop a pebble from height H, it reaches the ground with speed V if there is no air

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resistance. From what height should you drop it so it will reach the ground with twice speed?

A)

2H

B) 2H

C) 16H

D) 8H

E) 4H

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When you drop a pebble from height H, it reaches the ground with kinetic energy K if there is no

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air resistance. From what height should you drop it so it will reach the ground with twice as much

kinetic energy?

A)

2H

B) 2H

C) 16H

D) 8H

E) 4H

20)

Two objects, one of mass m and the other of mass 2m, are dropped from the top of a building. If

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there is no air resistance, when they hit the ground

1. both will have the same kinetic energy.
   1. the heavier one will have half the kinetic energy of the lighter one.
2. the heavier one will have four times the kinetic energy of the lighter one.
3. the heavier one will have twice the kinetic energy of the lighter one.
   1. the heavier one will have one-fourth the kinetic energy of the lighter one.

21) Swimmers at a water park have a choice of two frictionless water slides, as shown in the figure.

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Although both slides drop over the same height h, slide 1 is straight while slide 2 is curved, dropping quickly at first and then leveling out. How does the speed v₁ of a swimmer reaching the bottom of slide 1 compare with v₂, the speed of a swimmer reaching the end of slide 2?

1. v₁ < v₂
   1. v₁ > v₂
2. v₁ = v₂
3. The heavier swimmer will have a greater speed than the lighter swimmer, no matter which slide he uses.
   2. No simple relationship exists between v₁ and v₂.

22) Two frisky otters slide down frictionless hillsides of the same height but different slopes. The slope 22) of the hill of otter 1 is 30°, while the slope of the hill of otter 2 is 60°. If both start from rest, which

otter is moving faster when she reaches the bottom of her hill?

1. Otter 1 is moving faster.
   1. Otter 2 is moving faster.
2. The otter that took the shorter time is moving faster.
3. Both otters have the same speed at the bottom.
   1. The heavier otter is moving faster, no matter which hill she used.

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23) A lightweight object and a very heavy object are sliding with equal speeds along a level frictionless

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surface. They both slide up the same frictionless hill with no air resistance. Which object rises to a

greater height?

A) The heavy object, because it has more mass to carry it up the hill.

B) The lightweight object, because the force of gravity on it is less.

C) The light object, because gravity slows it down less.

D) The heavy object, because it has greater initial kinetic energy.

E) They both slide to exactly the same height.

24) A person stands on the edge of a cliff. She throws three identical rocks with the same speed. Rock

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X is thrown vertically upward, rock Y is thrown horizontally, and rock Z is thrown vertically

downward. If the ground at the base of the cliff is level, which rock hits the ground with the

greatest speed if there is no air resistance?

A) Rock X

B) Rock Y

C) Rock Z

D) They all hit the ground with the same speed.

25) Joe and Bill throw identical balls vertically upward. Joe throws his ball with an initial speed twice

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as high as Bill. If there is no air resistance, the maximum height of Joe’s ball will be

A) two times that of Bill’s ball.

B) four times that of Bill’s ball.

C) roughly 1.4 times that of Bill’s ball.

D) equal to that of Bill’s ball.

E) eight times that of Bill’s ball.

26) A stone can slide down one of four different frictionless ramps, as shown in the figure. For which

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ramp will the speed of the ball be the greatest at the bottom?

1. Ramp X
2. Ramp Y
3. Ramp Z
4. The speed of the ball will be the same for all ramps.

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27) A girl throws a stone from a bridge. Consider the following ways she might throw the stone. The

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speed of the stone as it leaves her hand is the same in each case.

Case A: Thrown straight up.

Case B:

Thrown straight down.

Case C:

Thrown out at an angle of 45° above horizontal.

Case D: Thrown straight out horizontally.

In which case will the speed of the stone be greatest when it hits the water below if there is no

significant air resistance?

A) Case A

B) Case B

C) Case C

D) Case D

E) The speed will be the same in all cases.

28) A heavy frog and a light frog jump straight up into the air. They push off in such away that they

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both have the same kinetic energy just as they leave the ground. Air resistance is negligible. Which

of the following statements about these frogs are correct? (There could be more than one correct

choice.)

1. Just as they leave the ground, the heavier frog is moving faster than the lighter frog.
2. Both frogs reach the same maximum height.
3. The lighter frog goes higher than the heavier frog.
4. They both leave the ground with the same speed.
5. Just as they leave the ground, the lighter frog is moving faster than the heavier frog.
6. The heavier frog goes higher than the lighter frog.

29) Two identical grasshoppers jump into the air with the same initial speed and experience no air

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resistance. Grasshopper A goes straight up, but grasshopper B goes up at a 66° angle above the horizontal. Which of the following statements about these grasshoppers are correct? (There could be more than one correct choice.)

1. At their highest point, both of them have the same amount of kinetic energy.
2. At their highest point, both of them have the same amount of gravitational potential energy.
3. At their highest point, grasshopper B is moving faster than grasshopper A.
4. At their highest point, both of them have the same amount of mechanical energy.
5. At their highest point, grasshopper A has more gravitational potential energy than grasshopper B.

30) A heavy rock and a light rock are dropped from the same height and experience no significant air

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resistance as they fall. Which of the following statements about these rocks are correct? (There could be more than one correct choice.)

1. Both rocks have the same speed when they reach the ground.
2. The heavier rock reaches the ground before the lighter rock.
3. Both rocks have the same kinetic energy when they reach the ground.
4. Just as they were released, both rocks had the same amount of gravitational potential energy.
5. When they reach the ground, the heavier rock has more kinetic energy than the lighter rock.

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31) A heavy stone and a light stone are released from rest in such away that they both have the same

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amount of gravitational potential energy just as they are released. Air resistance is negligibly small. Which of the following statements about these stones are correct? (There could be more than one correct choice.)

1. The stones must have been released from the same height.
2. The stones both have the same kinetic energy just as they reach the ground.
3. The stones both have the same speed just as they reach the ground.
4. The initial height of the light stone is greater than the initial height of the heavy stone.
5. Just as it reaches the ground, the light stone is traveling faster than the heavy stone.

32) A 1-kg ball is released from a height of 6 m, and a 2-kg ball is released from a height of 3 m. Air

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resistance is negligible as they fall. Which of the following statements about these balls are correct? (There could be more than one correct choice.)

1. As they reach the ground, the 1-kg ball will be moving faster than the 2-kg ball.
2. Both balls will take the same time to reach the ground.
3. Both balls will reach the ground with the same speed.
4. Both balls will reach the ground with the same kinetic energy.
5. As they reach the ground, the 1-kg ball will have more kinetic energy than the 2-kg ball because it was dropped from a greater height.

33) A heavy dart and a light dart are launched vertically by identical ideal springs. Both springs were

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initially compressed by the same amount. There is no significant air resistance. Which of the following statements about these darts are correct? (There could be more than one correct choice.)

1. The heavy dart goes higher than the light dart.
2. The light dart goes higher than the heavy dart.
3. At the maximum height, both darts have the same gravitational potential energy.
4. Both darts began moving upward with the same initial speed.
5. Both darts reach the same maximum height.

34) A heavy sled and a light sled, both moving horizontally with the same speed, suddenly slide onto

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a rough patch of snow and eventually come to a stop. The coefficient of kinetic friction between the sleds and the rough snow is the same for both of them. Which of the following statements about these sleds are correct? (There could be more than one correct choice.)

1. Both sleds will slide the same distance on the rough snow before stopping.
2. The friction from the snow will do more negative work on the heavy sled than on the light sled.
3. The friction from the snow will do the same amount of work on both sleds.
4. The light sled will slide farther on the rough snow than the heavy sled.
5. The heavy sled will slide farther on the rough snow than the light sled.

35) A heavy sled and a light sled, both moving horizontally with the same kinetic energy, suddenly

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slide onto a rough patch of snow and eventually come to a stop. The coefficient of kinetic friction between the sleds and the rough snow is the same for both of them. Which of the following statements about these sleds are correct? (There could be more than one correct choice.)

1. The light sled will slide farther on the rough snow than the heavy sled.
2. Both sleds will slide the same distance on the rough snow before stopping.
3. On the rough snow, the change in kinetic energy will be the same for both sleds.
4. The friction from the snow will do the same amount of work on both sleds.
5. The heavy sled will slide farther on the rough snow than the light sled.

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36)

If a stone is dropped with an initial gravitational potential energy of 100 J but reaches the ground

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with a kinetic energy of only 75 J, this is a violation of the principle of conservation of energy.

A) True

B) False

37)

If the units of your answer are kg · m²/s³, which of the following types of quantities could your

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answer be? (There could be more than one correct choice.)

1. work
2. potential energy
3. power
4. force
5. kinetic energy

38) Two cyclists who weigh the same and have identical bicycles ride up the same mountain, both

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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?

1. 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.
2. 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.
3. The average power exerted by Bob and Joe was the same, but Joe exerted more work in getting there.
4. Bob and Joe exerted the same amount of work, and the average power of each cyclist was also the same.

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

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A) the same as Jack’s power output.

B) twice Jack’s power output.

C) four times Jack’s power output.

D) one-half as much as Jack’s power output.

E) one-fourth as much as Jack’s power output.

40)

A force produces power P by doing work W in a time T. What power will be produced by a force

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that does six times as much work in half as much time?

A) 12P

B) 6P

C)

1

P

D) P

E)

1

P

6

12

41)

An ornament of mass 40.0 g is attached to a vertical ideal spring with a force constant (spring

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constant) of 20.0 N/m. The ornament is then lowered very slowly until the spring stops stretching.

How much does the spring stretch?

A) 0.0816 m

B) 0.00200 m

C) 0.0196 m

D) 0.800 m

E) 0.200 m

42)

A force of 30 N stretches a very light ideal spring 0.73 m from equilibrium. What is the force

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constant (spring constant) of the spring?

A) 34 N/m

B) 46 N/m

C) 22 N/m

D) 41 N/m

43)

A very light ideal spring stretches by 21.0 cm when it is used to hang a 135-N object. What is the

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weight of a piece of electronic equipment that would stretch the spring by 44.9 cm if you hung the

equipment using the spring?

A) 289 N

B) 405 N

C) 176 N

D)63N

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44)

An object attached to a spring is pulled across a horizontal frictionless surface. If the force constant

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(spring constant) of the spring is 45 N/m and the spring is stretched by 0.88 m when the object is

accelerating at 1.4 m/s², what is the mass of the object?

A) 36 kg

B) 28 kg

C) 24 kg

D) 31 kg

45)

A 3.0-kg brick rests on a perfectly smooth ramp inclined at 34° above the horizontal. The brick is

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kept from sliding down the plane by an ideal spring that is aligned with the surface and attached

to a wall above the brick. The spring has a spring constant (force constant) of 120 N/m. By how

much does the spring stretch with the brick attached?

A) 24 cm

B) 240 cm

C) 14 cm

D) 360 cm

E) 36 cm

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.

46) A very light ideal spring having a spring constant (force constant) of 8.2 N/cm is used to

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lift a 2.2-kg tool with an upward acceleration of 3.25 m/s². If the spring has negligible

length when it us not stretched, how long is it while it is pulling the tool upward?

47) A very light ideal spring with a spring constant (force constant) of 2.5 N/cm pulls

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horizontally on an 18-kg box that is resting on a horizontal floor. The coefficient of static

friction between the box and the floor is 0.65, and the coefficient of kinetic friction is 0.45.

(a) How long is the spring just as the box is ready to move?

(b) If the spring pulls the box along with a constant forward velocity of 1.75 m/s, how long

is the spring?

(c) How long is the spring if it pulls the box forward at a constant 2.75 m/s?

48) A very light ideal spring of spring constant (force constant) 2.5 N/cm is 15 cm long when

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nothing is attached to it. It is now used to pull horizontally on a 12.5-kg box on a perfectly

smooth horizontal floor. You observe that the box starts from rest and moves 96 cm during

the first 1.6 s of its motion with constant acceleration. How long is the spring during this

motion?

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

49)

How much work would a child do while pulling a 12-kg wagon a distance of 4.3 m with a 22 N

49)

force?

A) 67J

B)95J

C) 109 J

D)52J

50)

A child does 350 J of work while pulling a box from the ground up to his tree house at a steady

50)

speed with a light rope. The tree house is 4.0 m above the ground. What is the mass of the box?

A) 6.7 kg

B) 8.0 kg

C) 5.3 kg

D) 8.9 kg

51)

You carry a 7.0-kg bag of groceries 1.2 m above the ground at constant speed across a 2.7 m room.

51)

How much work do you do on the bag in the process?

A) 157 J

B) 185 J

C)82J

D) 0.00 J

52)

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

52)

stake by the ground is 828 N, how long is the stake?

A) 0.31 m

B) 0.23 m

C) 0.36 m

D) 0.41 m

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53)

A crane lifts a 425 kg steel beam vertically upward a distance of 95 m. How much work does the

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crane do on the beam if the beam accelerates upward at 1.8 m/s²? Neglect frictional forces.

A) 4.0 × 10^{5 J}

B) 2.7 × 10⁵J

C) 4.7 × 10⁵ J

D) 3.2 × 10⁵ J

54)

A traveler pulls on a suitcase strap at an angle 36° above the horizontal. If 555 J of work are done

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by the strap while moving the suitcase a horizontal distance of 15 m, what is the tension in the

strap?

A) 52N

B)56N

C) 46N

D)37N

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.

55) A 500-kg elevator is pulled upward with a constant force of 5500 N for a distance of 50.0

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m.

(a) What is the work done by the 5500-N force?

(b) What is the work done by gravity?

(c) What is the net work done on the elevator?