Problem 1 A piston cylinder device like the one shown in the figure contains 0.4 kg of air with an initial volume equal to 0.2 m. The piston has cross section Ap = 5 104 m and mass mp = 7.65 kg. Heat is supplied at a constant rate through the bottom of the cylinder; the lateral wall of the cylinder and the piston are made of a heat resistant material that can be considered a perfect thermal insulator (i.e., no heat transfer across the cylinder walls). The ambient atmospheric pressure surrounding the device is 100 kPa. As a result of applying heat, the internal energy of the gas increases by 22 kJ and the volume expands by 25%. Assume that there is no friction between the piston and the wall, and that the device is well sealed. Please answer the following: a) List the three most important assumptions and approximations that you will need and use to solve all questions below. You do not need to identify all these assumptions immediately. Identify those that you can right now then add more as you work through your analysis. Should this system be analyzed as a control volume (i.e., open system) or a control mass (i.e., closed system) b) c) Draw a diagram of the system that you will use in analyzing this physical process. Your schematic should include a system boundary and show all the different energy transfers via arrows across this boundary. d) e) Determine the initial pressure of the air inside the piston-cylinder device. Represent the initial (1) and final (2) states on a P-V diagram and the process line. Include values and units on each axis (kPa, m) f) Compute the work done by the air inside the cylinder on the piston during process 1-2, in kJ. g) Determine the final temperature of the air, in C. h) Evaluate the total heat transferred during the process, in kJ. Patm 100 kPa Air