Question

Two monoatomic ideal gases `1` and `2` of molecular masses `m_(1)` and `m_(2)` respectively are enclosed in separate containers kept at the same temperature. The ratio of the of sound in gas `1` to that in gas `2` is given by
A. `sqrt((m_(1))/(m_(2)))`
B. `sqrt((m_(2))/(m_(1)))`
C. `(m_(1))/(m_(2))`
D. `(m_(2))/(m_(1))`

Answer 1

Correct Answer - B
Speed of sound in a gas given by
`v=sqrt((gammaRT)/M)`
`v prop 1/(sqrt(M))`
`:. (v_(1))/(v_(2))=sqrt((M_(2))/(M_(1)))=sqrt((m_(2))/(m_(1))`
Here `gamma=(C_(p))/(C_(v))=5/3` for both the gases `(gamma_("monoatomic")=5/3)`