Q.7. 1. State the first law of thermodynamics. [03 marks] 2. As shown in Figure Q1, 10kg of steam contained within a piston-cylinder assembly undergoes an expansion from state 1 , where the specific internal energy is u1=2700kJ/kg, to state 2 , where u2=2600kJ/kg. During the process, there is heat transfer (Q) to the steam with a magnitude of 80kJ. Also, a paddle wheel transfers 18.5kJ of energy (Wpw) to the steam. There is no significant change in the kinetic or potential energy of the steam. Determine the energy transfer by work (W) from the steam to the piston during the process, in kJ. [07 marks] 3. What is the Clausius statement of the second law of thermodynamics? [03 marks] 4. Explain the Carnot cycle with the aid of P-V diagram clearly stating the processes of it. [05 marks] 5. A reversible power cycle receives energy QH from a reservoir at temperature TH and rejects Qc to a reservoir at temperature Tc. The work developed by the power cycle is used to drive a reversible heat pump that removes energy Qc from a reservoir at temperature Tc and rejects energy QH to a reservoir at temperature TH. 5.a. Develop an expression for the ratio QHQH in terms of the temperatures of the four reservoirs. [04 marks] 5.b. What must be the relationship of the temperatures TH,TC,,TC, and TH for QHQH to exceed a value of unity? [03 marks]