Astone is dropped at t = 0. a second stone, with 6 times the mass of the first, is dropped from the same point at t = 59 ms. (a) how far below the release point is the center of mass of the two stones at t = 430 ms? (neither stone has yet reached the ground.) (b) how fast is the center of mass of the two-stone system moving at that time?

Aperson gives a shopping cart an initial push along a horizontal floor to get it moving, and then lets go. the cart travels forward along the floor, gradually slowing as it moves. consider the horizontal force(s) on the cart while it is moving forward and slowing. which of the following statements is correct? (a) both a forward and a backward force are acting on the cart, but the forward force is larger. (b) only a forward force is acting which diminishes with time. (c) both a forward and a backward force are acting on the cart, but the backward force is larger. (d) only a backward force is acting, no forward force.