s to explain something, he or she always develops a model to work with. In the case of the golf stroke, it has become evident that comparing such an action to the snapping of a whip lends itself nicely to a deeper understanding. The model appropriate to the study of a whip, such as a bullwhip, would be a large number of small rods with flexible connections. This is important to understanding how the whip works. At the start of the motion, as the hand moves the handle of the whip, the momentum of the whip increases. The hand exerts a force on the whip handle for a time, producing, according to Newton's Second Law, an increase of momentum. This force moving the whip handle a few feet also does work on the whip, giving it kinetic energy. When the hand stops, the whip exerts a force on the hand, and this force in turn decreases the momentum of parts of the whip. Thus, momentum is not conserved because a force acts and there is no displacement because the hand remains still. During the stroke, successive parts of the whip are stopped, and t
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