Chapter 12, Problem 8P

What is the sound level of a sound whose intensity is 1.5 x 10-6 W/m²?

To determine

The intensity level of sound

Answer to Problem 8P

Solution:

Intensity at$1.5\times {10}^{-6}W/m^2$ is$61dB$

Explanation of Solution

Given:

$I=1.5\times {10}^{-6}W/m^2$

$dB=10\log \left(l/l_0\right)$

Threshold of hearing:${10}^{-12}w/m^2$

$\begin{array}{l}dB=10\log \left(1.5\times {10}^6/{10}^{-12}\right)\\ =10\log \left(1.5\times {10}^6\right)\end{array}$

$\begin{array}{l}dB=10\log 1.5+10\log {10}^6\end{array}$

$\begin{array}{l}=10\times 0.1+10\times 6\\ =61dB\end{array}$