Work, Energy, and Power — DPP 2

20 NEET questions from Work, Energy, and Power, with answers and explanations. Attempt it as a timed test to get scoring, accuracy breakdown and mistake tracking.

Attempt this test free 20 questions · 30 minutes · +80 marks
1
If $\vec { v } = ( 3 \hat { i } + 4 \hat { j } + 5 \hat { k } ) \mathrm { ms } ^ { - 1 }$ is the instantaneous velocity of a body of mass 1.50 kg , calculate its kinetic energy.
  1. A 30.5 J
  2. B 37.5 J
  3. C 45.5 J
  4. D 57.5 J
Show answer

Correct answer: B

2
A rope is used to lower vertically a block of mass M at a distance x at a constant downward acceleration g/2. The work done by the rope on the block is:
  1. A Mgx
  2. B $\frac { 1 } { 2 } M g x ^ { 2 }$
  3. C $- \frac { 1 } { 2 } M g x$
  4. D $\mathrm { Mgx } ^ { 2 }$
Show answer

Correct answer: C

3
Assertion (A): When a body moves in a circle the work done by the centripetal force is always zero.
Reason (R): Centripetal force is perpendicular to displacement at every instant.
  1. A Both Assertion (A) and Reason (R) are True and the Reason (R) is a correct explanation of the Assertion (A).
  2. B Both Assertion (A) and Reason (R) are True but Reason (R) is not a correct explanation of the Assertion (A).
  3. C Assertion (A) is True but the Reason (R) is False.
  4. D Assertion (A) is False but the Reason (R) is True.
Show answer

Correct answer: A

4
A rigid body of mass m kg is lifted uniformly by a man to a height of one metre in 30 sec. Another man lifts the same mass uniformly to the same height in 60 sec. The work done on the body against gravitation by them are in ratio
  1. A 1 : 2
  2. B 1 : 1
  3. C 2 : 1
  4. D 4 : 1
Show answer

Correct answer: B

5
A particle moves from position $\vec { r } _ { 1 } = 3 \hat { i } + 2 \hat { j } - 6 \hat { k }$ to position $\vec { r } _ { 2 } = 14 \hat { i } + 13 \hat { j } + 9 \hat { k }$ under the action of force $\vec { F } = 4 \hat { i } + \hat { j } + 3 \hat { k } N$. The work done by this force will be
  1. A 100 J
  2. B 50 J
  3. C 200 J
  4. D 75 J
Show answer

Correct answer: A

6
You lift a suitcase from the floor and keep it on a table. The work done by you on the suitcase depends on
  1. A The path taken by the suitcase
  2. B The time taken by you in doing so
  3. C The weight of the suitcase
  4. D Your weight.
Show answer

Correct answer: C

7
A stick of mass m and length l is pivoted at one end and is displaced through an angle θ. The increase in potential energy is
Work, Energy, and Power – NEET-6696
  1. A $m g \frac { l } { 2 } ( 1 - \cos \theta )$
  2. B $m g \frac { l } { 2 } ( 1 + \cos \theta )$
  3. C $m g \frac { l } { 2 } ( 1 - \sin \theta )$
  4. D $m g \frac { l } { 2 } ( 1 + \sin \theta )$
Show answer

Correct answer: A

8
A car and truck have same momentum. Which will have more kinetic energy?
  1. A Car
  2. B Truck
  3. C Both will have same kinetic energy
  4. D Data is insufficient to suggest
Show answer

Correct answer: A

9
A 50 kg man with 20 kg load on his head climbs up 20 steps, each of 0.25 m height. The work done by the man on the block during climbing is
  1. A 5 J
  2. B 350 J
  3. C 1000 J
  4. D 3540 J
Show answer

Correct answer: C

10
A position dependent force F = 7 - 2x + 3x$^{2}$ newton acts on a small body of mass 2 kg and displaces it from x = 0 to x = 5 m. The work done in joules is
  1. A 70
  2. B 270
  3. C 35
  4. D 135
Show answer

Correct answer: D

11
A body of mass 0.5 kg travels in a straight line with velocity $v = a x ^ { 3 / 2 }$ where $a = 5 \mathrm {~m} ^ { \frac { - 1 } { 2 } } \mathrm {~s} ^ { - 1 }$. The work is done by the net force during its displacement from x = 0 to x = 2 m is
  1. A 15 J
  2. B 50 J
  3. C 10 J
  4. D 100 J
Show answer

Correct answer: B

12
The power of a pump, which can pump 500 kg of water to height 100 m in 10 s is
  1. A 75 kW
  2. B 25 kW
  3. C 50 kW
  4. D 500 kW
Show answer

Correct answer: C

13
Assertion (A): Kinetic energy a body is quadrupled, when its velocity is doubled.
Reason (R): Kinetic energy is proportional to square of velocity.
  1. A Both Assertion (A) and Reason (R) are True and the Reason (R) is a correct explanation of the Assertion (A).
  2. B Both Assertion (A) and Reason (R) are True but Reason (R) is not a correct explanation of the Assertion (A).
  3. C Assertion (A) is True but the Reason (R) is False.
  4. D Assertion (A) is False but the Reason (R) is True.
Show answer

Correct answer: A

14
A particle is moving under the influence of a force given by F = Kx where K is a constant and x is the distance moved. The energy gained by the particle in moving from x = 0 to x = 5 is
  1. A 0.125 K
  2. B 0.185 K
  3. C 0.625 K
  4. D 12.5 K
Show answer

Correct answer: D

15
A rod of length 2 m and mass 0.5 kg is fixed at one end and allowed to hang vertically from a rigid support. Find the work done in raising the other end of the rod until it makes an angle of $60 ^ { \circ }$ with the vertical. (g = 10 ms$^{-2}$)
  1. A 1.5 J
  2. B 2 J
  3. C 2.5 J
  4. D 3.5 J
Show answer

Correct answer: C

16
Assertion (A): The potential energy can be defined only in conservative field.
Reason (R): The value of potential energy depends on the reference level (level of zero potential energy)
  1. A Both Assertion (A) and Reason (R) are True and the Reason (R) is a correct explanation of the Assertion (A).
  2. B Both Assertion (A) and Reason (R) are True but Reason (R) is not a correct explanation of the Assertion (A).
  3. C Assertion (A) is True but the Reason (R) is False.
  4. D Assertion (A) is False but the Reason (R) is True.
Show answer

Correct answer: B

17
A pump is used to pump a liquid of density ρ continuously through a pipe of cross section area A. If liquid is flowing with speed v, then power of pump is
  1. A $\frac { 1 } { 3 } \rho A v ^ { 2 }$
  2. B $\frac { 1 } { 2 } \rho A v ^ { 2 }$
  3. C $2 \rho A v ^ { 2 }$
  4. D $\frac { 1 } { 2 } \rho A v ^ { 3 }$
Show answer

Correct answer: D

18
Find the work done in moving a 50 kg block through a horizontal distance of 10 m by applying a force of 100 N which makes an angle of $60 ^ { \circ }$ with the horizontal.
  1. A 50 Joule
  2. B 50 ergs
  3. C 500 Joule
  4. D 500 ergs
Show answer

Correct answer: C

19
A force F = 5 + 2x acts on a body in x-direction where x is in metres and F in newton. Find the work done in displacing the body from x = 0 to x = 2 m.
  1. A 14 J
  2. B 18 J
  3. C 16 J
  4. D 20 J
Show answer

Correct answer: A

20
A person holds a bucket of mass 6 kg. He walks 7 m along the horizontal and then climbs a vertical distance of 5 m. The work done by the man is:
  1. A 300 J
  2. B 420 J
  3. C 720 J
  4. D 350 J
Show answer

Correct answer: A

Attempt this as a timed test

Reading answers is not the same as sitting the paper. Attempt it timed and you get your score, per-question timing, and the mistakes tracked for revision.

Start free

More Work, Energy, and Power tests

Work, Energy, and Power — DPP 1 20 Q Work, Energy, and Power — DPP 3 20 Q
All Work, Energy, and Power tests →