A 36.5 kg box initially at rest is pushed 4.30 m along a rough, horizontal floor with a constant applied horizontal force of 150 N. If the coefficient of friction between box and floor is 0.300, find the following.

(a) the work done by the applied force

(b) the energy loss due to friction,

(c) the work done by the normal force,

(d) the work done by gravity,

(e) the change in kinetic energy of the box, and

(f) the final speed of the box

(a) W = 645 J

(b) E = 461.9 J

(c) The work done by the normal force = 0 J as no displacement is taking place in that direction

(d) The work done by the gravitational force 0 J, as there is zero displacement in that direction too.

(e) ΔKE = 183 J

(f) v = 3.16 m/s

Explanation:

A 36.5 kg box initially at rest is pushed 4.3 m along a rough, horizontal floor with a constant applied horizontal force of 150 N. If the coefficient of friction between box and floor is 0.300, find the following.

(a) the work done by the applied force

W=F*d

W=150*4.3

W = 645 J

(b)

The increase in internal energy in the box-floor system due to friction

E=0.300*36.5*9.81*4.30

E = 461.9 J

(c)

The work done by the normal force = 0 J as no displacement is taking place in that direction

(d)

The work done by the gravitational force 0 J, as there is zero displacement in that direction too.

(e)

the change in kinetic energy of the box

ΔKE=645 - 461.9 J

ΔKE = 183 J

(f)

The final speed of the box

0.5*36.5*v^2 = 183 J

v^2 = 10

v = 3.16 m/s