1. The problem statement, all variables and given/known data Suppose I tie a ball of mass M to a string of length L and I swing the ball on the string in a vertical fashion. If the speed at the top is V1 and the speed at the bottom is V2. Would I have: Let T = tension in string (top) -T - Mg = -MV1^2/R (bottom) T - Mg = MV2^2/R So to find Mg (the force of gravity), I would add the 2 equations to get: -2Mg = MV2^2/R - MV1^2/R. But somehow that is wrong? Thanks.