The net work is equal to the change in kinetic energy. This relationship is called the work-energy theorem: \(Wnet = K. E._f − K. E._o \), where \(K. E._f\) is the final kinetic energy and \(K. E._o\) is the original kinetic energy. Potential energy, also referred to as stored energy, is the ability of a system to do work due to its position or internal structure. Change in potential energy is equal to work. The potential energy equations can also be derived from the integral form of work, \(\Delta P. E. = W = \int F \cdot dx\).