To define a continuously operating heat engine To use the Carnot analogy to define the second law of thermodynamics. To introduce the concept of thermal efficiency as applied to a heat engine. To use the Carnot conclusion to introduce the absolute temperature scale. To use the absolute temperature scale to introduce the concept of quality of energy. To show that the natural trend is for quality to decrease and entropy to increase. To introduce the reversed heat engine as a basis for a refrigerator. To introduce a continuously operating system operating on the Carnot cycle. To show that an irreversible process results in an increase in entropy. To introduce the adiabatic efficiency as applied to either a turbine or compressor.