8 15.3 The Carrnot heat engine and its efficiency 1. Carrnot cycle of ideal gases a→bQ= nrt\ c→d| EcnR Volume b→cTnV=TV d→aTmV=Tl 8 15.3 The Carrnot heat engine and its efficiency 2. The efficiency of carrnot cycle 2H-1o nRTHIn -nRTIn QH nITIn T the efficiency of Carrnot H cycle for ideal gases9 §15.3 The Carrnot heat engine and its efficiency 1. Carrnot cycle of ideal gases a b H H V V a →b Q = nRT ln d c C C V V c →d |Q |= nRT ln −1 −1 → = r C c r b c THVb T V −1 −1 → = r C d r d a THVa T V d c a b V V V V = H C H H C a b H d c C a b H H H C T T T T T V V nRT V V nRT V V nRT Q Q Q = − − = − = − = 1 ln ln ln | | ε H C T T ε =1− --the efficiency of Carrnot cycle for ideal gases 2. The efficiency of Carrnot cycle §15.3 The Carrnot heat engine and its efficiency