Final answer:
Simple harmonic motion is an oscillatory motion characterized by a restoring force proportional to the displacement, as seen in a mass-spring system or a simple pendulum.
Step-by-step explanation:
Simple harmonic motion (SHM) is a type of oscillatory motion where the restoring force is proportional to the displacement and is directed towards the equilibrium position. A classic example of a simple harmonic oscillator is a mass attached to a spring that follows Hooke's law, where the force exerted by the spring is proportional to the displacement from the equilibrium position.
Another common example is a simple pendulum, consisting of a mass (pendulum bob) hanging from a light wire or string, which for small angles (less than 15 degrees) oscillates with SHM around the equilibrium position. In SHM, the system oscillates with an equal displacement on either side of the equilibrium, and the maximum displacement is known as the amplitude. The motion is characteristic for its regularity and the way the system conserves energy as it moves between kinetic and potential states.