Pendulums-Relative Motion

A pendulum swings above a table. The table is also a pendulum that swings at right angles to and has the same period as the first pendulum. When both pendulums are set swinging at the same time, the observer sees the relative motions of the two pendulums in the frame of reference of the table. The relative motion can be linear, circular or elliptical depending on the phases and amplitudes of the pendulums. The visitor starts the pendulums swinging and controls their relative phase. This exhibit makes Lissajous patterns mechanically.