Physics - Sound Wave Question with Solution | TestHub

Let v₁and v₂be the speeds of sound in neon and water vapour respectively. Suppose that M₁ and M₂are the molecular weights of neon and water vapour respectively. If γ is the ratio of the two specific heats, then

$\frac{{\upsilon }_1}{{\upsilon }_2}=\sqrt{\frac{\text{RT }{\gamma }_{\text{neon}}}{{\text{M}}_1}}\times \sqrt{\frac{{\text{M}}_2}{\text{RT }{\gamma }_{\text{water vapour}}}}=\sqrt{\frac{{\text{M}}_2}{{\text{M}}_1}}\times \sqrt{\frac{{\gamma }_{\text{neon}}}{{\gamma }_{\text{water vapour}}}}$

Here,$M_1=2.02\times {10}^{-2} \mathrm{kg} {\mathrm{mole}}^{-1}$;

$M_2=1.8\times {10}^{-2} \mathrm{kg} {\mathrm{mole}}^{-1}$

$\therefore \frac{{\upsilon }_1}{{\upsilon }_2}=\sqrt{\frac{1·8\times 10^{-2}\times 5/3}{2·02\times 10^{-2}\times 4/3}}=1\text{.}1$