Question

HELP!!

A dresser of mass 60kg is pushed hard enough to set it in motion across a flat surface. The
coefficient of kinetic friction between the dresser and the surface is uk=0.52. What minimum
pushing force is needed to keep the box moving at a constant velocity?

Answer 1

Answer:312N

Explanation:

Force=coefficient of friction×reaction

Reaction=mass×acceleration due to gravity

Acceleration due to gravity=10m/s^2

Reaction=60×10=60N

Force=0.52×600

Force=312N

Answer 2

Answer:

The minimum force required is 312 N.

Explanation:

Friction is an oppositional force that tends to resist the motion of a body in relative to another when the two are in contact. Thus, it increases with the roughness of the surfaces considered, this determines the coefficient of friction.

From the question, we are given; mass = 60 Kg, Uk = 0.52 = μ

But,

                        F = μR

where f is the force applied, μ is the coefficient of friction and R the reaction on the surface.

           R = mg

               = 60 × 10    

assuming that the force of gravity is 10$ms^{-2}$

           R = 600 Kg$ms^{-2}$

So that,

                F = μR

    ⇒         F  =  0.52 × 600

                     = 312 Kg$ms^{-2}$

    Thus the minimum force required to make the box move with constant velocity is 312 N.