An 18" high superstructure, from which a pendulum may be hung, mounts on this disk, which measures 10" in diameter and 1/2" thick. The disk comes complete with bearing post, weight, hex key, and a variety of experimental possibilities. A groove machined around the perimeter of the disk holds a string for rotational dynamics experiments. If the disk is placed on a bearing post, the pendulum will continue to swing in the same plane while the disk rotates, graphically illustrating a Foucault Pendulum. Set the pendulum oscillating while the disk is floating on an air table to illustrate Newton's Third Law of Motion. The disk may be used for experiments in acceleration, force, and torque.