Chapter Seven – Oscillations
To and fro motion of an object about its mean position is known as oscillatory motion. Periodic motion is a motion which repeats itself after regular intervals of time.
If acceleration of a body is directly proportional to the displacement and is always directed towards its mean position, such a motion is called simple harmonic motion.
The quantity which indicate the state of motion is called phase. In oscillating system total energy remains conserved. A body executes free oscillation if it vibrates on its natural frequency. When external force interferes in free oscillation, forced oscillations occur. The process in which energy is dissipated from the oscillating system is called damping.