One kg of air initially at 20°C and 1 kg /cm2 is to be reversibly compressed to a final state of 10 kg/cm2 and 100°C. This may be achieved by any of the following three processes:
(i) Heating at constant volume followed by cooling at constant pressure.
(ii) Isothermal compression followed by heating at constant pressure.
(iii) Adiabatic compression followed by cooling at constant volume.
Assuming air to be behave like an ideal gas with cv = 0.1729 kcal/ kg°C and cp = 0.2412 kcal/kg°C, determine the work required, the heat transferred and the internal energy changes in the processes. Sketch the path followed by each of the processes on a single diagram.