Question

A body of weight 50 N is placed on a smooth surface. If the force required to move the body on the surface is 30 N the coefficient of friction is

• A. 0.6
• B. 1.2
• C. 0.3
• D. 1.67

Answer 1

Answer: (A)

0.6

If $\mu$ be the coefficient of friction, the friction force $f=\mu mg$

As friction opposes the motion, so the magnitude of friction force and appling force will be same here.

So, $\mu mg=30$ or $\mu =\frac{30}{50}=0.6$