Simple Harmonic Motion

Definition
Type of vibratory motion in which acceleration of body is directly
proportional its displacement and the acceleration is always directed towards the equilibrium (mean) position is called simple harmonic motion
Acceleration a – displacement
a – x
Negative sign indicates that acceleration and displacement are opposite in direction.

Basic conditions to execute simple harmonic motion
Basic conditions to execute simple harmonic motion are as under:

• There must be an elastic restoring force acting on the system.
• The system must have inertia.
• The acceleration of the system should be directly proportional to its displacement and is always directed to mean position i.e. a x

Examples of simple harmonic motion

• Motion of a body attached to the end of an elastic spring.
• Motion of the bob is a simple pendulum if it is given small displacement.
• Motion of an elastic strip.
• Motion of the prongs of a tuning fork.
• Motion of the wire of a guitar or violin

Characteristics of simple harmonic motion

• The motion must be vibratory.
• The motion should be a periodic motion.
• The restoring force should be directly proportional to the displacement of the body from its mean position.