Question

5kg of hydrogen in a closed movable container undergoes a few processes. Initially the pressure of hydrogen is 300kPa and its temperature is 35°C is expanding until the volume become twice the initial while maintaining the temperature. Later, by controlling the pressure, the volume need to be reduce to 10m3. Then 800kJ of heat is being added to the system without producing any work. Again hydrogen will be heated with PVn=cont until the pressure is equal to the initial pressure and T=130K. The hydrogen later will be undergoing a process with n=1 until volume become half. Hydrogen later will be continued to heated until the twice the pressure with n=7.5 Finally, the air undergoes polytropic cooling to the initial state.

      i.     Sketch the P-V diagram
    ii.      Find all P’s, V’s and T’s
   iii.      Calculate all Q’s
   iv.      Determine the nett work of the cycle