## Question

Find out the ratio of the velocity of sound in helium and in nitrogen gases at 300 K temperature. Molecular weights of helium and nitrogen are 4 and 28 respectively.

### Solution

2.9

The speed of sound in a gas is,

Where T is absolute temperature of the gas and *M* is molecular weight of the gas. The speed of sound in helium is

And that in nitrogen is

We know that for a mono-atomic gas (as He) the value of γ is 5/3, and for a diatomic gas (as N) is 7/5.

Given: M_{N} = 28 and M_{He} = 4.

#### SIMILAR QUESTIONS

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