$p \left(\frac{ m }{ d }\right)^{\gamma}=$ const
$\frac{ p }{ d ^{\gamma}}=$ const $\quad \frac{ d _{2}}{ d _{1}}=32$
$\frac{ p _{1}}{ p _{2}}=\left(\frac{ d _{1}}{ d _{2}}\right)^{\gamma}=\left(\frac{1}{32}\right)^{7 / 5}=\frac{1}{128}$
$\frac{ T _{1}}{ T _{2}}=\frac{ P _{1} V _{1}}{ P _{2} V _{2}}=\frac{1}{128} 32=\frac{1}{4}$


${P_A} = 3 \times {10^4}Pa,\;{P_B} = 8 \times {10^4}Pa$ and ${V_A} = 2 \times {10^{ - 3}}{m^3},\;{V_D} = 5 \times {10^{ - 3}}{m^3}$
In process $AB$, $600 J$ of heat is added to the system and in process $BC, 200 J $ of heat is added to the system. The change in internal energy of the system in process $ AC$ would be ...... $J$