Question

At what temperature will the speed of sound in air become double of its speed at $0^{\circ }C$ ?

• A. ${619}^{0}C$
• B. ${719}^{0}C$
• C. ${819}^{0}C$
• D. ${919}^{0}C$

Answer 1

Answer: (C)

${819}^{0}C$

$\frac{v_1}{v_0}=\sqrt{\frac{T_1}{T_0}}$
$\therefore$ $\frac{{2v}_0}{v_0}=\sqrt{\frac{T_1}{273}}$ $(\because v_1=2v_0$)
$\Rightarrow$ $4=\frac{T_t}{273}$
$\Rightarrow$ $T_t=4\times 273=1092K$ $=1092-273=819C$