\( \Rightarrow \sqrt {\frac{{{T_A}}}{{{M_A}}}} = 2\sqrt {\frac{{{T_B}}}{{{M_B}}}} \)
\( \Rightarrow \sqrt {\frac{{3R{T_A}}}{{{M_A}}}} = 2\sqrt {\frac{{3RT}}{{{M_B}}}} \)
\( \Rightarrow {C_A} = 2{C_B}\)
\( \Rightarrow \frac{{{C_A}}}{{{C_B}}} = 2\)
$[k_B\, = 1 .4\times10^{-23}\,J/K;\, m_{He}\, = 7\times10^{-27}\,kg]$