Question

A block of mass 2kg is placed on the floor. The coefficient static friction is 0.4. A force of friction 2.5N is applied on the block. Calculate the force of friction between the floor and the block.

Answer 1

Actually, 2.5N should be external force applied not the frictional force as we have to calculate that.

The frictional force can be calculated using the following formula

f = μ_s.m.g

here

μ_s = 0.4

m = 2 kg

g = 9.81 m/s2

thus, we get

f = 0.4 x 2 x 9.81

thus, the static frictional force between the block and floor will be

f = 7.848 N