A man pushes a $$10 kg$$ box at a constant velocity over a distance of $$4 m$$ on a rough horizontal surface. The coefficient of kinetic friction between the box and the floor is $$0.3$$. Calculate the work done by the person on the box?
The correct option is C $$120 J$$
Given : $$m=10kg$$ $$\mu =0.3$$ $$S = 4$$ m
As the velocity of the box is constant, thus net force acting on the box must be equal to zero.
$$\therefore$$ Horizontal force applied by man $$F = f = \mu_k mg = 0.3 \times 10 \times 10 = 30$$ $$N$$