heat engine that uses in its thermodynamic cycle a polyatomic gas (CV = 3R) as its working fluid. The pressures at states 1 and 3 are given. Determine the engine and Carnot efficiencies. Is this heat engine a realistic engine?

WHAT IS THE TOTAL CHANGE IN ENTROPY OF THE UNIVERSE IN RUNNING THIS SYSTEM? (please only answer if your 100% correct) (show work)

Consider a variation of the Carnot cycle in a closed system with 10 kg of pure water operating. ranging between temperatures of 130 C and 350 ◦C. State 1 is a saturated liquid. Process 1-2 is a isothermal expansion with a supply of QH = 10 MJ. Process 2-3 is an adiabatic expansion with isentropic efficiency from 0.75 to minimum temperature. Process 3-4 is a compression isothermal, and the 4-1 process is a reversible adiabatic compression. Calculate: a. The pressure p2, the bonds x4 and x3, and the specific entropies s1 and s3; b. The work in each expansion and compression process; c. The heat rejected QL, the net work produced Wl i q and the yield η of the cycle; d. The entropy generated Sg in the cycle

A proposed cyclic heat engine will accept 300 J of heat from a hot reservoir at 800 K, output 250 J of work to the surroundings, and reject 50 J of heat to a cold reservoir at 300 K. According to the 2nd law of thermodynamics, which of the following statements is correct? The system is possible but irreversible. The system is impossible. The system is possible and reversible.