Question

A box is pulled 6 meters across the ground at a constant velocity by a horizontally applied force of 50 newtons. At the same time, kinetic friction acts on the box as it slides so that it eventually stops when the pulling force stops. What is the magnitude of the frictional force? How much work does the frictional force do? What is the net work done on the box?

Answer 1

Answer:

(a) Friction force = 50 N

(b) Work done by friction = 300 j

(c) Net work done = 0 j

Explanation:

We have given that the box is pulled by 6 meter so d = 6 m

Force applied on the box F = 60 N

We have have given that velocity is constant so acceleration will be zero

So to applied force will be utilized in balancing the friction force

So friction force $F_{friction}=50N$

Work done by friction force $W_{friction}=F_{friction}\times d=50\times 6=300j$

Work done by applied force $W=F\times d=50\times 6=300j$

So net work done = 300-300 = 0 j