The velocity of sound hydrogen is $1224\,\,{\rm{m}}{{\rm{s}}^{ - 1}}$. Its velocity in mixture of hydrogen and oxygen containing $4$ parts by volume of hydrogen and $1$ part oxygen is

If the temperature of the atmosphere is increased, the following character of the sound wave is effected

Two waves travelling in a medium in the x-direction are represented by , ${y_1} = A\sin \left( {\alpha t - \beta x} \right)$ and ${y_2} = A\cos \left( {\beta x + \alpha t - \pi /4} \right)$ where ${y_1}\;\,\,and\,\,{\rm{ }}{y_2}$ are the displacements of the particles of the medium, t is time, and  $\alpha \,and\,\beta$ are constants. The two waves have different

The fundamental frequency of a sonometre wire is $n$. If its radius is doubled and its tension becomes half, the material of the wire remains same, the new fundamental frequency will be

A stone is dropped in a well which is $19.6\,\,m$ deep. Echo sound is heard after $2.06\,\,\sec$ (after dropping) then the velocity of sound is

From a point source, if amplitude of waves at a distance $r$ is A, its amplitude at a distance $2r$ will be

The intensity of sound from a radio at a distance of $2\,\,metres$ from its speaker is $1 imes {10^{ - 2}}\mu W/{m^2}$. The intensity at a distance of $10\,\,metres$ would be

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

A sound absorber attenuates the sound level by $20{\rm{ }}dB$. The intensity decreases by a factor of

The intensity of sound increases at night due to

When the temperature of an ideal gas is increased by $600\,\,K$, the velocity of sound in the gas becomes $\sqrt 3$ times the initial velocity in it. The initial temperature of the gas is