Work, Energy and Power Test Online MCQs

1. Two bodies of masses m and 4m are moving with equal kinetic energy. Then the ratio of their linear momentum will be:

2. If the water falls from a dam into a turbine wheel 19.5 m below, then the velocity of water at the turbine is: (take g = 9.8 m/sec²)

3. Which one of the following is true?

4. A bullet is fired form a riffle. If the riffle recoils freely, then the kinetic energy of the rifle will be:

5. A particle of mass m moving with velocity v collides with a stationary particle of mass 2m. Then the speed of the system after collision is:

6. A shell of mass m moving with velocity v suddenly breaks into 2 pieces. The part having mass m/3 remains stationary. The velocity of other part will be:

7. For inelastic collision between two spherical rigid bodies:

8. If the water falls from a dam into a turbine wheel 19.6 m below, then the velocity of water at the turbines, is (take g = 9.8 m/s²)

9. A bullet of mass 10g leaves a riffle at an initial velocity of 1000 m/sec and strikes the earth at the same level with a velocity of 500 m/sec. The work in overcoming the resistance of air will be:

10. Two bodies of masses 0.1 kg and velocities they stick together. In 10 sec the combined mass travels

11. A body of mass 5 kg has momentum of 10 kg m/sec. When a force of 0.2 N is applied on it for 10 sec, the change in its kinetic energy is

12. A ball of mass 10 kg is moving with a velocity of 10 m/s. It strikes another ball of mass 5 kg, which is moving in the same direction with a velocity of 4 m/s. If the collision is elastic their velocities after collision will be respectively

13. A vertical spring with force constant k is fixed on a table. A ball of mass m at a height h above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance d. The net work done in the process is

14. A force newton acts on a body and displaced it by meter. The work done by the force is:

15. A block of mass 10 kg is moving in x-direction with a constant speed of 10 m/sec. It is subjected to a retarding force F = -0. 1x joule/meter during its travel from x = 20 meter to x = 30 meter. Its final kinetic energy will be: