Answer to Question #194295 in Classical Mechanics for Showrav Roy

Question

Compare simple harmonic motion with a motion which is harmonic but not simple harmonic motion.

Answer 1

Any motion which repeats itself can be called harmonic motion and so simple harmonic motion is in the set of harmonic motions.

In mechanics it can be interpreted as the motion of a mass acted on by a restoring force which is proportional to the displacement of the mass from a fixed point.

Simple harmonic motion has important properties, for example, the period of oscillation does not depend on the amplitude of the motion and lots of systems do undergo simple harmonic motion even if sometimes it is an approximation.

A good example of the difference between harmonic motion and simple harmonic motion is the simple pendulum.

The simple pendulum undergoes harmonic motion, however for small angles of oscillation it does approximately undergo simple harmonic motion.