# 50+ Work-Energy Theorem MCQs and Answers

Work Energy Theorem MCQ and Answers are must for the aspirants who are preparing for various competitive examination. It covers the concept of Work, Energy and Power which is very important for any competitive exams. This Law of Work, Energy and Power topic is given most importance in various competitive exams like JEE Main, JEE Advanced, NEET, AIIMS etc.

## Work Energy Theorem MCQ

#### 1. The change in the total energy of a body moving because of work being done on it is attributed by the change in kinetic energy only when ______

a) It moves extremely slowly

b) It moves with a very high velocity

c) It moves on an equipotential surface

d) It moves with a positive acceleration

a) 0

b) 10

c) 15

d) 20

#### 3. A projectile has both change in kinetic and potential energy. Still the work done calculated between any two points is zero. This is due to _________

a) Presence of no external force

b) No displacement

c) The displacement being in both vertical and horizontal directions

d) Inter-conversion of kinetic and potential energies

#### 4. A body having 7 kg of mass moves slowly and covers a vertical height of 14 m. What is the work done in Joules and what force causes this work? Take g = 10 m/s2.

a) 980, gravity

b) 980, force acting opposite to gravity

c) 1000, gravity

d) 1000, force acting opposite to gravity

#### 5. The total energy of a system moving under the action of a conservative force changes by 50 J. Which of the following statements are correct with regards to the amount of work done?

a) Amount of work done = 50 J

b) Amount of work done < 50 J

c) Amount of work done > 50 J

d) Amount of work done <= 50 J

#### 6. A body of mass 2 Kg, initially at rest, moves under the influence of an external force of magnitude 4 N on plane ground. What is the work done by the force and the change in kinetic energy in the first 10 seconds?

a) 400 J, 400 J

b) -400 J, 400 J

c) 400 J, -400 J

d) -400 J, -400 J

#### 7. A body moving with a constant velocity on normal ground initially has an energy of 1000 J. If the final energy is 800 J, what is the work done and which force causes this work?

a) 200 J, gravity

b) -200 J, friction

c) 200 J, friction

d) -200 J, gravity

#### 8. According to the work-energy theorem, total change in energy is equal to the _______

a) Total work done

b) Half of the total work done

c) Total work done added with frictional losses

d) Square of the total work done

a) 50 kJ

b) -50 kJ

c) 25 kJ

d) 10 kJ

#### 10. The total energy change of a body which covers a vertical height is constituted completely by the potential energy change only when ______

a) It moves slowly

b) It moves quickly

c) It moves for some time, then rests, then moves again

d) It moves with a decreasing velocity