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Compound Pendulum

Compound Pendulum. A simple pendulum is understood theoretically to mean an infinitely small mass suspended from a point by a thread without mass. Such an arrangement cannot exist, and can only be approximated. Any distribution of mass oscillating about a point from which it is suspended forms a compound pendulum. Its period of oscillation is equal to that of a simple pendulum of determinate length; this is called the equivalent simple pendulum. In every compound pendulum there exist pairs of points, either of which may be made the centres of suspension without changing the rate of swinging.