Question

A boy walks over a rough surface, then the angle between the force of friction and the instantaneous velocity of the boy is

• A. ${90}^0$
• B. ${180}^0$
• C. ${60}^0$
• D. $0^0$

Answer 1

The correct option is D $0^0$

The angle between instantaneous velocity and friction will be zero, i.e., both these vectors are in the same direction as depicted in the following figure.