question_answer

According to Grahman's law at a given temperature, the ratio of the rates of diffusion \[{{r}_{A}}/{{r}_{B}}\] of gases A and B is given by       [IIT 1998]

A)                 \[({{P}_{A}}/{{P}_{B}}){{({{M}_{A}}/{{M}_{B}})}^{1/2}}\]

B)                 \[({{M}_{A}}/{{M}_{B}}){{({{P}_{A}}/{{P}_{B}})}^{1/2}}\]

C)                 \[({{P}_{A}}/{{P}_{B}}){{({{M}_{B}}/{{M}_{A}})}^{1/2}}\]

D)                 \[({{M}_{A}}/{{M}_{B}}){{({{P}_{B}}/{{P}_{A}})}^{1/2}}\] (where P and M are the pressures and molecular weights of gases A and B respectively)