$A$ steel rod of length $100 \, cm$ is clamped at the middle. The frequency of the fundamental mode for the longitudinal vibrations of the rod is ..... $kHz$ (Speed of sound in steel $= 5 \, km \, s^{-1}$)

The temperature at which the speed of sound in air becomes double of its value at $27^\circ C$ is ... $^\circ C$

$A$ plane wave of sound traveling in air is incident upon a plane surface of a liquid. The angle of incidence is $60^{\circ}.$ The speed of sound in air is $300 \, m/s$ and in the liquid it is $600 \, m/s.$ Assume Snell's law to be valid for sound waves.

$A$ stone is dropped into a well that is $19.6\,m$ deep. If the echo is heard after $2.06\,s$ of dropping the stone,calculate the velocity of sound in $m/s$.

$v_1$ and $v_2$ are the velocities of sound at the same temperature in two monoatomic gases of densities $\rho_1$ and $\rho_2$ respectively. If $\frac{\rho_1}{\rho_2} = \frac{1}{4}$,then the ratio of velocities $v_1$ and $v_2$ will be

What is the ratio of the velocity of sound in hydrogen $\left(\gamma=\frac{7}{5}\right)$ to that in helium $\left(\gamma=\frac{5}{3}\right)$ at the same temperature? (Molecular weight of hydrogen and helium is $2$ and $4$ respectively)