One half of a mole of air is taken through the following processes in a closed piston-cylinder arrangement. From the initial state (V1 = 10 L, p1 = 1 atm) the gas is expanded at constant pressure to a volume of 20 L. It is then heated at constant volume until its final pressure is 2 atm.
a) Draw these processes on T - V and p - V coordinates, including numerical labels for each state
b) Find the total input of heat in these processes, in J. Assume that the specific heat of air at constant pressure depends on the temperature as given by Eq. 3-48 and use values from Table A-21 to solve this part.
c) Find the total input of heat in these processes, in J, using values from Table A-22.
d) Discuss any differences you find between the methods. Explain why any differences arise.