Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A sound absorber attenuates the sound level by $20\, dB$. The intensity decreases by a factor of

NEETNEET 2022

Solution:

Let intensity of sound be $I$ and $I^{\prime}$.
Loudness of sound initially
$\beta_1=10 \log \left(\frac{I}{I_0}\right)$
Later, $\beta_2=10 \log \left(\frac{I^{\prime}}{I_0}\right)$
Given, $\beta_2-\beta_1=20$
$\therefore 20 =10 \log \left(\frac{I^{\prime}}{I}\right)$
$I^{\prime} =100 I$