To demonstrate the conversion of kinetic energy into potential energy and vice versa. It consists of a rotating axle which is held in horizontal position by two threads attached to a metal strip and is moved upwards by winding of thread. When the wheel is released from its wound position, wheel acquires kinetic energy on its way down. At the lowest position when the threads are full unwound, they start rewinding around the axle of wheel and rises upward again. The whole assembly is fitted on a stand.
