Question

Block A (mass 40 kg) and block B (mass 80 kg) are connected by a string of negligible mass as shown in the figure. The pulley is frictionless and has a negligible mass. If the coefficient of kinetic friction between block A and the incline is μk = 0.27 and the blocks are released from rest, determine the change in the kinetic energy of block A as it moves from C to D, a distance of 21 m up the incline.