I.

Introduction

Oscillation, in physics, chemistry, and engineering, repeated motion back and forth past a central neutral position, or position of equilibrium. A single motion from one extreme position to the other and back, passing through the neutral position twice, is called a cycle. The number of cycles per second, or hertz (Hz), is known as the frequency of the oscillation.

A swinging pendulum or a plucked violin string eventually comes to rest if no further forces act upon it. The force that causes it to stop oscillating is called damping. Often the damping forces are frictional, but other damping forces, such as electrical or magnetic ones, might affect an oscillating system. See Electricity; Electronics; Magnetism.