Question

A wooden box weighing 150 N is sliding at a constant rate over a concrete sidewalk. The force required to pull the box at a steady rate is 78 N. What is the coefficient of friction?

Answer 1

Box is moving at constant velocity. Therefore, net force on the wooden box is zero.

f = μN
78 = μ(mg)
μ = 78/150 = 0.52
Therefore, coefficient of friction is 0.52

Answer 2

The coefficient of friction is 0.52

Step-by-step explanation:

Weight of the box, W = N = 150 N

The force required to pull the box at a steady rate is 78 N, F = 78 N

In horizontal direction, the net force acting on the box is given by :

`F-\mu N=0`

`F=\mu N`

`\mu=(F)/(N)`

`\mu=(78)/(150)`

`\mu=0.52`

So, the coefficient of friction is 0.52. Hence, this is the required solution.