Question

A body slipping on a rough horizontal on a rough horizontal plane moves with a deceleration of $4-0$ m/s What is the coefficient of kinetic friction between the block and the plane ?

• A. 0.2
• B. 0.4
• C. 0.6
• D. 0.8

Answer 1

The correct option is B 0.4

The frictional force=F=ma

where m is mass and a= deceleration of the body $=4.0\frac{m}{s^2}$

so $f=4mN$

Normal force= Weight of the body=mg

So coefficient of Kinetic friction $=\frac{4m}{mg}=\frac{4}{g}=\frac{4}{10}=0.4$

Hence the coefficient of kinetic friction between the block and the plane is 0.4.