To
demonstrate the conservation of mechanical energy. All parts are made in
metal. When the wheel is rotated by hand to the top and released, its
potential energy turns into kinetic energy (rotation) as it falls. After
the wheel reaches its bottom position, the kinetic energy changes back to
potential energy when it moves up again. This process continues until the
total energy is lost because of friction. Dimensions, 18 × 2 × 5";