Series. Two engines are connected in series such that engine 1 operates between tem- peratures T₁ and Tm with T₁ > Tm while engine 2 operates between temperatures Tm and T2 with Tm > T₂. Engine 1 absorbs Q₁ from heat bath at T₁, performs work W₁, then dumps the remaining Qm to heat bath at Tm. Engine 2 absorbs the same dumped heat Qm from heat bath at Tm, performs work W₂, then finally dumps the remaining Q₂ into the heat bath at T₂. Show that the effective efficiency of the two engine in series is given by, Eeff. = €1 + €2- €1 €2, (2) where €1= W₁/Q1 and 2 = = W₂/Qm.
