Question
A block of mass 4 kg lies on a rough horizontal surface. The coefficient of friction between the block and surface is 0.6. What is the minimum horizontal force required to set the block into motion?
Solution
Given, 
Mass of the block, m = 4kg
Coefficient of friction,
∴ Force of limiting friction is,
= 23.52 N
The minimum force required to set the body into motion is equal to limiting friction. Thus, force required to set the body into motion is 23.52N.
