Physics 1028 Study Guide - Final Guide: Init
Document Summary
We use the conservation of energy concept, written as: (1) for which we first identify the initial and final instants. Choose them such that the information available at one instant is complete, and that the unknown parameter occurs at the other instant. It doesn"t matter, however, on which side of eq. We choose as the initial instant the moment of release when both objects are at rest. For the final instant we choose the instant at which the object of mass m has fallen 30 cm since we are asked about the total kinetic energy (unknown variable) at that point. The initial kinetic energy is zero since both objects start from rest. The initial potential energy can be chosen arbitrarily since there is no predetermined origin along the vertical axis which defines y = 0 in epot = m g y for either object.
