Choose a specific example of a situation in which the energy transformation is W → K.
a. A ball rolls into a horizontal spring on the level ground, compressing it. The spring is not part of the system, but an external object. b. You cease pushing a box across a rough, level surface, and it slows down to a stop on the rough surface. Both the box and the rough floor are parts of the system. c. You push a hockey puck across a very smooth ice, speeding it up. You are not part of the system, and friction and drag can both be ignored. d. You push a box across a rough, level surface, so that the box does not speed up or slow down. Both the box and the surface are parts of the system, but you are not