Thermodynamics Part 3

Given The final pressure of the adiabatic process, $p_{f}=200\;\mathrm{N}/\mathrm{m}^{2}$ The initial pressure of the adiabatic process, $p_{i}=100\;\mathrm{N}/\mathrm{m}^{2}$ The initial volume of the adiabatic process, $V_{1}=4\;\mathrm{m}^{3}$ The final volume of the adiabatic process, $V_{f}=3\;\mathrm{m}^{3}$ We know that, for an adiabatic process $W=\frac{p_{f}V_{f}-p_{i}V_{i}}{1-\gamma}$ $\Rightarrow\;\; W=\frac{200(3)-100(4)}{1-1.4}$ $\Rightarrow\;\; W=-500\;\mathrm{J}$ So, the work done by an adiabatic process is $500\;\mathrm{J}$ and negative sign represents the work done on the system.