Question

Which of the following graphs correctly represents the variation of velocity of sound $\left(v\right)$ with the pressure $\left(P\right)$ of a gas at constant temperature?

• A.
• B.
• C.
• D.

Answer 1

The correct option is D

We know that the velocity of sound in a gas is given by,

$V=\sqrt{\frac{\gamma RT}{M}}$

where $\gamma$ is the adiabatic index, $R$ is universal gas constant, $T$ is absolute temperature and $M$ is molecular mass of the gas.

At constant temperature, we can see that the velocity is independent of pressure variation.

Hence, velocity of sound will remain constant as pressure changes.

So, option $\left(d\right)$ is correct.