Question

A horizontal force of 20 N is applied to a block of mass 4 kg resting on a rough horizontal table. If the block does not move on the table, how much frictional force the table is applying on the block? What would be the coefficient of friction between the block and the table?

Answer 1

Explanation:

Mass, m=4 kg

Static friction is a self-adjusting force.

So, normal reaction = 4g

Since the block is at rest, so limiting friction force ≥ applied force.

i.e., μs mg≥20

⇒μmg≥20

μs≥0.5