A60.0-kg person running at an initial speed of 4.00 m/s jumps onto a 120-kg cart initially at rest (fig. p9.69). the person slides on the cart’s top surface and finally comes to rest relative to the cart. the coefficient of kinetic friction between the person and the cart is 0.400. friction between the cart and ground can be ignored. (a) find the final velocity of the person and cart relative to the ground. (b) find the friction force acting on the person while he is sliding across the top surface of the cart. (c) how long does the friction force act on the person? (d) find the change in momentum of the person and the change in momentum of the cart. (e) determine the displacement of the person relative to the ground while he is sliding on the cart. (f) determine the displacement of the cart relative to the ground while the person is sliding. (g) find the change in kinetic energy of the person. (h) find the change in kinetic energy of the cart. (i) explain why the answers to (g) and (h) differ. (what kind of collision is this one, and what accounts for the loss of mechanical energy? )