Periodic Motion: Any motion that repeats itself at regular
intervals of time is called peridoic motion.
Oscillatory Motion: An periodic
motion in which a body moves to and fro over the same path is called
Simple Harmonic Motion: An oscillatory motion in which the particle is acted upon by a force
which is directed towards a fixed point in the path of the motion and which
is proportional to the displacement of the body from the fixed point, is
called simple harmonic motion.
Amplitude: The maximum displacement of the body from
the mean position.
Time Period: The time taken for one complete
Frequency: The number of oscillation per unit time.
Phase: The state of vibration of the particle in
Phase Constant or Epoch: The initial phase
(at t = 0) of the vibratory particle.
Angular S.H.M.: Oscillatory motion of a body in which the
body is acted upon by a restoring couple which is directly proportional to
its angular displacement from the equilibrium position and directed opposite
to the angular displacement.