The entropy production or for nitrogen, an ideal gas, is 0.360 kJ/kg K when it is throttled from an initial pressure of 400 kPa. Determine (a) the final pressure, in kilopascals, to which the gas is throttled and (b) the ratio of the inlet to outlet area if the inlet and exit velocities are identical

Water at the initial pressure and temperature of P1 = 40 bar and T1 = 553.15K, respectively, is cooled at constant volume, while heat is transferred to the surroundings at T0= 288.15K. At the end of the cooling process, the pressure is P2 = 9 bar. Questions: (a) Calculate the entropy change of the water during the process. (b) Calculate the entropy produced during the process.

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A rigid tank containing air is subjected to a reversible process in which it is heated from its initial state at T1 = 600 K and P1 = 1.5 bar to a final state with P, = 4.352 psi. Assuming that air can be modelled as an ideal gas, determine the specific change in entropy As12. (kJ/kg-K). Your Answer: