Answer:[tex]I_2=0.618\times 10^{-7} W/m^2[/tex]
Explanation:
Given
Distance between source and receiver [tex]d_1=3 m[/tex]
Sound Intensity [tex]I_1=1.1\times 10^{-7} W/m^2[/tex]
Distance of of second observer [tex]d_2=4 m[/tex]
Intensity varies as
[tex]I\propto \frac{1}{d^2}[/tex]
using this
[tex]I=\frac{k}{d^2}[/tex]
[tex]\frac{I_1}{I_2}=\frac{d_2^2}{d_1^2}[/tex]
[tex]\frac{1.1\times 10^{-7}}{I_2}=\frac{4^2}{3^2}[/tex]
[tex]I_2=0.75^2\times 1.1\times 10^{-7}[/tex]
[tex]I_2=0.618\times 10^{-7} W/m^2[/tex]
