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(2) (2) (a) Should the radiator of a car be analysed as a closed system or an open system? Explain your answer. (b) When is the energy crossing the boundaries of a closed system heat and when is it work? Explain your answer. (c) Draw a P-v diagram for different thermodynamic processes and explain their differences. (d) A section of a pipeline runs above ground and is supported by vertical steel shafts (k = 25 W/m K) thatrare 1 m long and have a cross-sectional area of 0.005 m. Under normal operating conditions, the temperature variation along the length of the shaft is known to be governed by an expression of the form: (4) T = 100 - 150x + 10x2 Where T and x have units of °C and meter, respectively. Assume the temperature is uniform over the shaft cross section. Evaluate the temperature and conduction heat rate at the shaft-pipeline joint (x=0) and at the shaft-ground interface (x=1 m). (10) (e) A frictionless piston-cylinder device contains 2 kg of nitrogen at 100 kPa and 300 K. Nitrogen is now compressed slowly according to the relation PV14 constant until it reaches a final temperature of 360 K. Calculate the work done during the process. (7)