The 20-lb block is moving to the left with a speed of 4 ft/s at time t = 0, at which time the force P is applied as shown on the graph. If the...

The 20-lb block is moving to the left with a speed of 4 ft/s at time t = 0, at which time the force P is applied as shown on the graph. If the coefficient of kinetic friction mu_k = 0-2. determine the time t at which the block comes to a stop. Answer. t = 0.305 s.