Question

Sound velocity is maximum in
A. ${{H}_{2}}$
B. ${{N}_{2}}$
C. $He$
D. ${{O}_{2}}$

Answer 1

The concept of sound velocity in a medium is to be used here. sound is a longitudinal wave it needs medium to travel and hence density of medium plays an important role in determining the speed of sound in that medium
As different gases have different molecular structure, speed of sound will be different with hydrogen being the lightest and oxygen being heaviest offers more hindrance to the path of sound and hence sound’s velocity.

Complete step by step answer:
The speed of sound depends on the medium.as the medium particles vibrate to and fro and transfer the vibration to the nearest particle resulting in travelling of sound wave from any medium.
The formula for sound velocity in a medium is,
$v=\sqrt{\dfrac{\gamma RT}{M}}$, Where $R$ is universal gas constant,$T$ is temperature and $\gamma$ is adiabatic gas constant.
So, velocity of sound is inversely proportional to the molecular mass of the gaseous medium in which it is travelling in.
We are given $4$ gases out of which hydrogen gas is the lightest with molecular mass of $1u$ and oxygen being the heaviest with molecular mass of $16u$ and hence the sound velocity will be maximum in hydrogen gas medium ${{H}_{2}}$.

So, the correct answer is “Option A”.

Note: Transverse waves are those waves in which the oscillations are perpendicular to the wave or to the direction of propagation.
The speed of sound is highest in solid medium because medium particles are closely packed resulting in faster transfer of wave’s energy from one particle to another.