Audible, Infra and Ultra sound

AUDIBLE WAVE:

The human ear is sensitive to sound waves of frequency between 20Hz to 20kHz. This range is known as the audible range and these waves are known as audible waves.

e.g. Waves produced by vibrating sitar, guitar, organ pipes, flutes, shehnai, etc.

INFRASONIC WAVE:

A longitudinal elastic wave whose frequency is below the audible range i.e. 20Hz is called an infrasonic wave.

It is generally generated by a large source.

e.g. Earthquake.

ULTRASONIC WAVE:

A longitudinal wave whose frequency is above the upper limit of audible range i.e. 20 kHz, is called an ultrasonic wave. It is generated by very small sources.

e.g. Quartz crystal

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