Question

The temperature at which the speed of sound in air becomes double of its value at 27${}^o$ C?

• A. -123 ${}^o$ C
• B. 927 ${}^o$ C
• C. 327 ${}^o$ C
• D. 54 ${}^o$ C

Answer 1

Answer: (B)

927 ${}^o$ C

Speed of sound in air is given as $\sqrt{\frac{3RT}{M_0}}$

Thus the speed $V\propto \sqrt{T}$

Thus is velocity becomes double, the temperature must go to four times its initial value.

Initial temperature=$27+273=300K$

Hence final temparature=$1200K={927}^{\circ }C$