Question

At NTP the density of a gas is 1.3 kg/m³ and the velocity of sound propagation in the gas is 330 m/s. The degree of freedom of gas molecule is-

• A. 3
• B. 5
• C. 6
• D. 7

Answer 1

Answer: (B)

5

Answer 2

V = $\sqrt{\gamma P/\rho}$

330 = $\sqrt{\gamma \times \frac{1 \times 10^{5}}{1.3}}$

$\frac{(33)^{2} \times 100 \times 1.3}{1 \times 10^{5}}$ = g

$\frac{1.089 \times 10^{3} \times 10^{2} \times 1.3}{1 \times 10^{5}}$ = g

$\frac{2}{f}$ + 1 = g = 1.4 = 7/5

$\frac{2}{f}$ = 2/5

f = 5