CALC A heal engine Operates using the cycle shown in Fig. P20.41. The working substance is 2 00 mol of helium gas, which reaches a maximum temperature of 327°C. Assume the helium can be treated as an ideal gas. Process bc is isothermal. The pressure in states a and c is 100 × 105 Pa. and the pressure in state b is 3.00 × 105 Pa. (a) How much heat enters the gas and how much leaves the gas each cycle? (b) How much work does the engine do each cycle, and what is its efficiency? (c) Compare this engine’s efficiency with the maximum possible efficiency attainable with the hot and cold reservoirs used by this cycle.
Figure P20.41
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