Concept:At the same temperature, the mean square velocity of gas molecules depends on the molecular mass and is shared equally along the three coordinate axes.
Explanation:For gas A, the mean square of the x-component of velocity is
ω2.
The total mean square velocity is the sum of the squares of the three components, so
vA2​​=3ω2.
From kinetic theory,
vA2​​=m3kT​.
Thus,
3ω2=m3kT​, which gives
ω2=mkT​.
For gas B, the mean square velocity is given as
V2.
Since the mass of each molecule of gas B is
2m, we have
V2=2m3kT​.
Dividing the two results,
V2ω2​=3kT/(2m)kT/m​=32​.
Answer:The required value of
V2ω2​ is
32​, which is the ratio
2:3.
Therefore, the correct option is B.