Given:
I = 30dB
P = 66 × [tex]10^{-9}[/tex] Pa
Solution:
Formula used:
I = [tex]20\log_{10}(\frac{P}{P_{o}})[/tex] (1)
where,
I = intensity of sound
P = absolute pressure
[tex]P_{o}[/tex] = reference pressure
Using Eqn (1), we get:
[tex]30 = 20\log _{10}\frac{66\times 10^{-9}}{P^{o}}[/tex]
[tex]P_{o}[/tex] = [tex]\frac{66\times 10^{-9}}{10^{1.5}}[/tex]
[tex]P_{o}[/tex] = 2.08 × [tex]10^{-9}[/tex] Pa