Calculate the bulk modulus of air from the following data about a sound wave of wavelength 35 cm travelling in air. The pressure at a point varies between `(1.0 x 10^5+-14)` Pa and the particles of the air vibrate in simple harmonic motion of amplitude` 5.5 x 10^-6m`.

Options

A. `2.4 xx 10^-5 N//m^2`
B. `1.4 xx 10^-4 N//m^2`
C. `1.4 xx 10^-5 N//m^2`
D. `1.4 xx 10^-4 N//m^2`

Answer

C

Explanation

We know that
Bulk modulus
`B=(/_\p)/((/_\v/v)=(p_0lamda)/(2piS_0)`
`where P_0=` pressure amplitude
`P_0=1.0xx10^5`
`rarr displacement amplitude`
`rarr S_0=5.5xx10^-6m`
`rarr B=((14xx35xx10^-2m)/(2pi(5.5)xx10^-6m))`
`=1.4xx10^5N/m^2`