\(\frac{{{T_1}}}{{{T_2}}} = {\left( {\frac{{{V_2}}}{{{V_1}}}} \right)^{\gamma - 1}}\)or \({\left( {\frac{1}{2}} \right)^{\gamma - 1}} = \sqrt {\frac{1}{2}} \)
\(\therefore \gamma - 1 = \frac{1}{2}\)or \(\gamma = \frac{3}{2}\)
\(\therefore P{V^{3/2}}\)= constant