A 55-kg box rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.30. A horizontal 140-n force is applied to the box. What is the friction force on the box?

The friction force on the box is 161.7 N

Explanation:

given information:

m = 55 kg

μs = 0.30

F = 140 N

To calculate the friction force, we use the following formula:

F (friction) = μs N,

N is normal force

N - W = 0

N = W

= m g

Thus,

F (friction) = μs N

= μs m g

= 0.3 x 55 x 9.8

= 161.7 N