The speed of sound in Oxygen $( O_2)$ at a certain temperature is 460 m/s. The speed of sound in helium at the same temperature will be…..$ms^{- 1}$ . (Assume both gases to be ideal)
$ \nu = \sqrt { \gamma P \over \rho } = \sqrt { \gamma RT \over M} $ $ \therefore { \nu_2 \over \nu_1 } = \sqrt { { \gamma_{He} \over 4 } \times { 32 \over \gamma_{02} } }$