Pressure Wave Derivation

Q.

For sound waves in air with frequency 1000 Hz, a displacement amplitude of $1.2\times {10}^{-8}$ m produces a pressure amplitude of $3.0\times {10}^{-2}$ Pa. What is the wavelength of these waves? (Provided Bulk modulus of Air = $1.42\times {10}^{5}Pa$)

1. 0.3 m

2. 0.4 m

3. 0.36 m

4. None of these

Q. A sound wave of wavelength $50\text{cm}$ travels in a gas medium. If the difference between the maximum and minimum pressures at a given point is $5\times {10}^{-3}{\text{N/m}}^2$ and the amplitude of vibration of the particles of the medium is $5\times {10}^{-10}\text{m}$, find bulk modulus of the medium.

1. ${10}^5{\text{N/m}}^2$
2. $2\times {10}^5{\text{N/m}}^2$
3. $3\times {10}^5{\text{N/m}}^2$
4. $4\times {10}^5{\text{N/m}}^2$

Q.

when a stone is dropped in water which waves are formed?? transverse or longitudinal??

Q. For the pressure variation in a longitudinal wave represented as $P=P_o\cos (\omega t-kx)$, the density $\left(\rho \right)$ equation for the given medium is best represented by
(${\rho }_o$ is the density of the medium at pressure $P_o$)

1. $\rho ={\rho }_o\sin (\omega t-kx)$
2. $\rho =-{\rho }_o\sin (\omega t-kx)$
3. $\rho ={\rho }_o\cos (\omega t-kx)$
4. $\rho =-{\rho }_o\cos (\omega t-kx)$

Q.

For sound waves in air with frequency 1000 Hz, a displacement amplitude of $1.2\times {10}^{-8}$ m produces a pressure amplitude of $3.0\times {10}^{-2}$ Pa. What is the wavelength of these waves? (Provided Bulk modulus of Air = $1.42\times {10}^{5}Pa$)

1. 0.3 m

2. 0.4 m

3. 0.36 m

4. None of these