What is simple harmonic motion ?

Inmechanicsandphysics,simple harmonic motionis a type ofperiodic motionwhere the restoring force is directly proportional to the displacement. It can serve as amathematical modelof a variety of motions, such as the oscillation of a spring. In addition, other phenomena can be approximated by simple harmonic motion, including the motion of asimple pendulumas well asmolecular vibration. Simple harmonic motion is typified by the motion of a mass on a spring when it is subject to the linear elastic restoring force given byHooke's Law. The motion is sinusoidal in time and demonstrates a single resonant frequency. In order for simple harmonic motion to take place, the net force of the object at the end of the pendulum must be proportional to the displacement, i.e.