Question

A uniform sphere of mass 20 kg and radius 10 cm is placed on a rough horizontal surface. The coefficient of friction between the sphere and the surface is 0.5. A horizontal force of magnitude 14 N is applied on the sphere as shown. The friction force acting on the sphere will be ​

Answer 1

Friction force acting on the sphere is 14 N.

Explanation:

Given:

 mass = 20 kg

  radius of sphere = 10 cm = 0.1 m

  Coefficient of friction u = 0.5

  Horizontal force = 14 N

Force of friction ,  F = uN

          Normal force N = mg

                    ⇒ F = umg

                       ⇒  F = 0.5 x 20 x 9.8

                           = 98 N

Force of friction is greater than horizontal force

So, horizontal force  = force of friction = 14 N.