Sound waves

A Sound is a form of energy that creates the sensation of hearing in our ears. This energy s in the form of waves. A medium is necessary for the propagation of sound waves. Sound waves give rise to a chain of compression (place of higher density) and rarefaction (place of lower density) in the medium.

The particles of the medium move parallel to the direction that the pulse moves. This type of wave is a longitudinal wave. Longitudinal waves are always characterized by particle motion being parallel to wave motion. A sound wave traveling through air is a classic example of a longitudinal wave.

A transverse wave is a wave in which particles of the medium move in a direction perpendicular to the direction that the wave moves.

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