As a budding mechanical engineer, you are called upon to design a Carnal engine that has 2.00 moles of He gas (see Table 15.41) as its working substance and that operates from a high-temperature reservoir at 500°C. The engine is to lift a 15.0 kg weight 2.00 m per cycle, using 500 J of heat input. The gas in the engine chamber can have a minimum volume of 5.00 L during the cycle. (a) Draw a pV diagram for this cycle. In your diagram, show where heat enters and leaves the gas. (b) What must be the temperature of the cold reservoir? (c) What is the thermal efficiency of the engine? (d) How much heat energy does this engine waste per cycle? (e) What is the maximum pressure that the gas chamber Will have to withstand?
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