The intensity of a sound wave while passing through an elastic medium falls down to 10% as it covers one metre distance through the medium. If the initial intensity of the sound wave was 100 decibels, its value after it has passed through 3 metre thickness of the medium will be :

The intensity of a sound wave while passing through an elastic medium

1.	The intensity of a sound wave while passing through an elastic medium falls down to 10% as it covers one metre distance through the medium. If the initial intensity of the sound wave was 100 decibels, its value after it has passed through 3 metre thickness of the medium will be :
Answer» 60 DECIBEL 72.9 decibel 81 decibel 70 decibel. Solution :Here `I_(3) = (90)/(100) xx (90)/(100 xx (90)/(100) xx 100` dB `I_(3) ` = 72.9 dB. Correct choice is b.

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The intensity of a sound wave while passing through an elastic medium falls down to 10% as it covers one metre distance through the medium. If the initial intensity of the sound wave was 100 decibels, its value after it has passed through 3 metre thickness of the medium will be :

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