A closed system loses energy by heat transfer at the rate of 10kJ/s. If the system operates at steady state, explain whether work was done on the system or by the system.

Five kg of water is contained in a piston–cylinder assembly, initially at 5 bar and 300°C. The water is slowly heated at constant pressure to a final state. The heat transfer for the process is 3260 kJ and kinetic and potential energy effects are negligible.Determine the final volume, in m3, and the work for the process, in kJ.

Give an example of in the absence of any work interactions, the energy change of a system is equal to the net heat transfer.

In a piston cylinder system, a fluid at 0.8 bar occupying 0.07 m³ is compressed reversibly to a pressure of 10.2 bar and specific volume of 0.6 m³/kg according to the law p = c. The fluid then expands reversibly according to the law pv² = c to 1.1 bar. A reversible cooling at constant volume then restores the fluid back to initial state. Calculate the net work for the process in Joules. To 3 d.p. and insert the unit symbol joules.