Consider the sound wave travelling in ideal gases of He , CH 4 and CO 2 . All the gases have the same ratio P/ρ , where P is the pressure and ρ is the density. The ratio of the speed of sound through the gases v He : v CH 4 : v CO 2 is given by

Physics · Sound Waves

JEE Main 2025 — 4 April, Morning Shift — Question 48

Consider the sound wave travelling in ideal gases of $\mathrm{He}, \mathrm{CH}_{4}$ and

$\mathrm{CO}_{2}$ . All the gases have the same ratio $\frac{P}{\rho}$ , where $P$ is the pressure

and $\rho$ is the density. The ratio of the speed of sound through the gases

$v_{\mathrm{He}}: v_{\mathrm{CH}_{4}}: v_{\mathrm{CO}_{2}}$ is given by

$v=\sqrt{\frac{u P}{\rho}}$

v_{\mathrm{He}}: v_{\mathrm{CH}_{4}}: v_{\mathrm{CO}_{2}}=\sqrt{\frac{5}{3}}: \sqrt{\frac{4}{3}}: \sqrt{\frac{7}{5}}

Answer key and solution verified before publishing.

Start with this question, then two more from the same chapter — with a tutor that explains every step. Free.