Question

The velocity of sound in a gas is 30 m s${}^{-1}$ at 27${}^{\circ }$ C. What is the velocity of the sound in the same gas at 127${}^{\circ }$ C?

• A. 20 m s${}^{-1}$
• B. 40 m s${}^{-1}$
• C. 20 $\sqrt{3}$ m s${}^{-1}$
• D. 60 m s${}^{-1}$

Answer 1

The correct option is C 20 $\sqrt{3}$ m s${}^{-1}$

$\frac{V_{27}}{V_{127}}=\sqrt{\frac{(27+273)}{(127+273)}}$
$\frac{30}{V_{127}}=\sqrt{\frac{300}{400}}$
$V_{127}=34.64m{s}^{-1}$
or
$20\sqrt{3}m{s}^{-1}$