two-dimensional (usually vertical) plane. In other words, the complex pendulum can move to anywhere within the sphere, which has the radius of the total length of the two pendulums. However, for a small angle, the double pendulum can act similarly to the simple pendulum because the motion is determined by sine and cosine functions as well. Examples The image shows a marine clock with motor springs and double pendulum sheel. See also Cymatics Lissajous curve Double pendulum Resonance References Classical mechanics Articles containing video clips