Correct Answer - A
Suppose `n_(1)` molecules have `v_(1)` velocity and `n_(2)` molecules have `v_(2) velocity. Then,
`v_(av) = (n_1 v_1 + n_2 v_2)/(n_2 + n_2)`
But, `v_(rms) = sqrt((n_1 v_1^2 + n_2 v_2^2)/(n_1 +n_2)`
Now, `v_(rms) ge v_(av)` because `v_1" and" v_2` may be in opposite directions also.