Question

Assertion: Frictional force is independent of the velocity of the body.
Reason: Friction is due to irregularities.
A) Both assertion and reason are correct and reason is the correct explanation of assertion.
B) Both assertion and reason are correct but reason is not the correct explanation for assertion.
C) Assertion is correct but reason is incorrect.
D) Both assertion and reason is incorrect.

Answer 1

Hint: Frictional force is defined as the resistive force which works on the opposite direction of the motion of the body and the friction force depends upon the coefficient of friction and the weight of the body.

Complete step by step solution:
It is given in the problem an assertive and reason type question in which the assertion is that frictional force is independent of the velocity of the body and the reason is given as friction is due to irregularities.

The given assertion is true as the frictional force is independent of the velocity of the body; the frictional force depends upon the weight and coefficient of friction of the body and the reason is given that the friction is due to irregularities which is also correct as the friction force on the smooth surface becomes zero, the irregularities on the surface is only responsible for the friction force to arise. The friction force arises when there is interlocking of the irregularities of the surface and the body which is in motion. Friction can be decreased if the surface irregularities are decreased.

The given assertion is correct, also the reason is correct and also the reason is the correct explanation for the assertion.

The correct answer for this problem is option A.

Note: The frictional force is the force which allows us to walk on the surface of earth. Wherever the body moves it applies force in the backwards direction then the friction force again applies force on the body and this is how anybody moves.