Attaching two of these devices end to end creates a chaotic device whose trajectories trace out part of a topological torus. The generic equation of motion for these devices is "theta-double-dot equals negative k times sine theta", assuming there are no extended masses present, as in the "compound" type of this device. One type of these devices picks up a geometric phase as the Earth rotates, causing it to precess; that type is named for Foucault. The period of these devices equals "2 pi times root (length over small g)". For 10 points, name th
Attaching two of these devices end to end creates a chaotic device whose trajectories trace out part of a topological torus. The generic equation of motion for these devices is "theta-double-dot equals negative k times sine theta", assuming there are no extended masses present, as in the "compound" type of this device. One type of these devices picks up a geometric phase as the Earth rotates, causing it to precess; that type is named for Foucault. The period of these devices equals "2 pi times root (length over small g)". For 10 points, name this simple device consisting of a weight suspended from a string, which exhibit approximate simple harmonic motion.
Attaching two of these devices end to end creates a chaotic device whose trajectories trace out part of a topological torus.
pendulum [accept simple pendulum; accept Foucault's pendulum; accept double pendulum] 