1) An inventor claims that he has designed a heat engine that operates between a high...

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1) An inventor claims that he has designed a heat engine that operates between a high temperature thermal energy reservoir at temperature 800C and a low temperature thermal energy reservoir at temperature 25C, and has a thermal efficiency of 75%. Is his claim valid or not? Why? 2) Consider a reversible heat engine that operates between a high temperature thermal energy reservoir at temperature TH, and a low temperature thermal energy reservoir at temperature T = 30C. Calculate and plot Wnet,out/QH for 100C TH 800C for this reversible heat engine. 3) A heat pump operates on a Carnot heat pump cycle with a COP of 12. It consumes 3 kW of power to keep the temperature inside the house at 25C. What is the temperature outside the house, and that is the heat transfer rate provided by the heat pump to the house? 4) 2 kg of Refrigerant 134-a is contained in a constant volume tank as a saturated vapor. When it is heated, the refrigerant pressure and temperature become 400 kPa and 50C, respectively. Determine the change of entropy of the refrigerant during this process. If the heat transfer is coming from a thermal energy reservoir at 100C, what is the change in entropy of the thermal energy reservoir, and sum of the changes in entropy of refrigerant and the thermal energy reservoir? 1) An inventor claims that he has designed a heat engine that operates between a high temperature thermal energy reservoir at temperature 800C and a low temperature thermal energy reservoir at temperature 25C, and has a thermal efficiency of 75%. Is his claim valid or not? Why? 2) Consider a reversible heat engine that operates between a high temperature thermal energy reservoir at temperature TH, and a low temperature thermal energy reservoir at temperature T = 30C. Calculate and plot Wnet,out/QH for 100C TH 800C for this reversible heat engine. 3) A heat pump operates on a Carnot heat pump cycle with a COP of 12. It consumes 3 kW of power to keep the temperature inside the house at 25C. What is the temperature outside the house, and that is the heat transfer rate provided by the heat pump to the house? 4) 2 kg of Refrigerant 134-a is contained in a constant volume tank as a saturated vapor. When it is heated, the refrigerant pressure and temperature become 400 kPa and 50C, respectively. Determine the change of entropy of the refrigerant during this process. If the heat transfer is coming from a thermal energy reservoir at 100C, what is the change in entropy of the thermal energy reservoir, and sum of the changes in entropy of refrigerant and the thermal energy reservoir?