Two sound waves have equal displacement amplitudes, but wave 1 has two-thirds the frequency of wave 2. What is the ratio of the intensity of wave 1 to the intensity of wave 2?

Respuesta :

Answer:

[tex]\dfrac{I_1}{I_2}=\dfrac{4}{9}[/tex]

Explanation:

c = Speed of wave

[tex]\rho[/tex] = Density of medium

A = Area

[tex]\nu[/tex] = Frequency

[tex]\nu_1=\dfrac{2}{3}\nu_2[/tex]

Intensity of sound is given by

[tex]I=\dfrac{1}{2}\rho c(A\omega)^2\\\Rightarrow I=\dfrac{1}{2}\rho c(A2\pi \nu)^2[/tex]

So,

[tex]I\propto \nu^2[/tex]

We get

[tex]\dfrac{I_1}{I_2}=\dfrac{\nu_1^2}{\nu_2^2}\\\Rightarrow \dfrac{I_1}{I_2}=\dfrac{\dfrac{2}{3}^2\nu_2^2}{\nu_2^2}\\\Rightarrow \dfrac{I_1}{I_2}=\dfrac{4}{9}[/tex]

The ratio is [tex]\dfrac{I_1}{I_2}=\dfrac{4}{9}[/tex]