mechanics (mass, force, acceleration, work, energy, momentum, velocity) - Category wise Question and Answer Practice Test with Solutions

Question : 16

Assertion :
A man gets completely exhausted in trying to push a stationary wall.
Reason :
Work done by the man on the wall is zero.

a) If Assertion is correct but Reason is incorrect.

b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

c) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

d) If Assertion is incorrect but Reason is correct.

Question : 17 [Uttarakhand Lower Sub. (Pre) 2010]

The energy of wind is

a) Electrical

b) Only kinetic

c) Only potential

d) Potential and kinetic both

Question : 18 [PSC (Pre) 2019]

Which physical quantity is represented by the ratio of momentum and velocity of the body?

a) Mass

b) Acceleration

c) Velocity

d) Force

Question : 19

A missile is launched with a velocity less than escape velocity. The sum of its kinetic and potential energies is

a) positive

b) negative

c) zero

d) may be positive, negative or zero

Question : 20

When you compress a coil spring you do work on it. The elastic potential energy

a) disappears

b) decreases

c) increases

d) remains the same