The speed of sound in oxygen `(O_2)` at a certain temperature is `460ms^-1`. The speed of sound in helium (He) at the same temperature will be (assume both gases to be ideal)

Options

A. `500 ms^(-1)`
B. `650 ms^(-1)`
C. `330 ms^(-1)`
D. `460 ms^(-1)`

Answer

B

Explanation

`V_(0_(2)) = sqrt((gammaRT)/(M)) = sqrt((7)/(5)(RT)/(32)) = 460`
`V_(H_(e)) = sqrt((gammaRT)/(M)) = sqrt(((5)/(3)RT)/(4)) = sqrt((5)/(12)460xx460xx32xx(5)/(7)) = 1419 m//s`