A heat engine takes 2.0 moles of an ideal gas through the reversible cycle abca
ID: 2252632 • Letter: A
Question
A heat engine takes 2.0 moles of an ideal gas through the reversible cycle abca, on the pV diagram shown in the figure. The path bc is an isothermal process. The temperature at c is 820 K, and the volumes at a and c are 0.010 m3 and 0.16 m3, respectively. The molar heat capacity at constant volume, of the gas, is 37 J/mol
A heat engine takes 2.0 moles of an ideal gas through the reversible cycle abca, on the pV diagram shown in the figure. The path bc is an isothermal process. The temperature at c is 820 K, and the volumes at a and c are 0.010 m3 and 0.16 m3, respectively. The molar heat capacity at constant volume, of the gas, is 37 J/mol·K, and the ideal gas constant is R = 8.314 J/(mol?K). The thermal efficiency of the engine is closest to..........Explanation / Answer
The figure is not given.
Heat lost in siothermal process=n*R*T*ln(V2/V1)=2*8.314*820*ln(0.16/0.01)=37.804 KJ
Heat Gained in constant volume heat addition provess= n*Cv*T=2*37*820=60.680 KJ
work=heat added-heat lost=22.876 KJ
Therefore efficiency= Work done/Heat added=22.876/60.680= 0.37699