A force is applied to a 22.5 kg object causing it to move at a constant velocity of 4.2 m/s with a coefficient of friction of 0.44. Suddenly, the applied force is removed, causing friction to be the only force acting on the object. How long will it take the object to come to rest.

M*g = 22.5 * 9.8 = 220.5 N. = Wt. of object = Normal force(Fn).

Fk = u*Fn = 0.44 * 220.5 = 97 N. = Force of kinetic friction.

Fap-Fk = M*a.
0-97 = 22.5a
a = -4.3 m/s^2.

V = Vo + a*t.
0 = 4.2 - 4.3t
t = ?.