An ultrasonic signal sent from $SONAR$ returns to it after reflection from a rock after a lapse of $1 \, s$. If the velocity of ultrasound in water is $1600 \, m/s$,the depth of the rock in water is ..... $m$.

The following phenomenon cannot be observed for sound waves:

The ratio of the velocity of sound in hydrogen gas $(\gamma = 7/5)$ to that in helium gas $(\gamma = 5/3)$ at the same temperature will be

Write Newton's equation for the speed of a sound wave in air.

What is the effect of humidity on sound waves when humidity increases?

The depth of the sea is measured by means of an echo. If the time between the moment the sound is produced and received is $3.52 \,s$, then the depth of the sea is (The compressibility of sea water is $4.84 \times 10^{-10} \,m^2 \,N^{-1}$ and its density is $1024 \,kg \,m^{-3}$): (in $km$)