Question

define audible Infra and ultrasonic sound​

Answer 1

A longitudinal wave whose frequency is above the upper limit of audible range i.e. 20 kHz, is called ultrasonic wave. It is generated by very small sources. (c) Infrasonic wave : A longitudinal elastic wave whose frequency is below the audible range i.e. 20 Hz, is called an infrasonic wave.

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Answer 2

Heya here is ur answer..

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Sound is only audible to the average human ear if the frequency of sound lies between 20hz to 20khz.

$infrasonic \: sound$

$sound \: waves \: with \: frequencies \\ \: less \: than \: 20hz \: are \: called \\ \: infrasonic \: sound.$

$ultrasonic \: sound$

$sound \: waves \: with \: frequencies \\ higher \: than \: 20khz \: are \: called \: \\ ultrasonic \: sound.$

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