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CHAPTER 5 The Second Law of Thermodynamics
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CHAPTER

5

The Second Law of Thermodynamics

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FIGURE 5-9Part of the heat received by a heat engine is converted to work, while the rest is rejected to a sink.

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FIGURE 5-10Schematic of a steam power plant.

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FIGURE 5-14Schematic of a heat engine.

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FIGURE 5-16A heat-engine cycle cannot becompleted without rejecting someheat to a low-temperature sink.

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FIGURE 5-23The efficiency of a cooking appliance represents the fraction of the energy supplied to the appliance that is transferred to the food.

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FIGURE 5-25Basic components of a refrigerationsystem and typical operating conditions.

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FIGURE 5-26The objective of a refrigerator is to remove QL from the cooled space.

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FIGURE 5-27The objective of a heat pump is to supply heat QH into the warmer space.

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FIGURE 5-33Proof that the violation of the Kelvin-Planck statement leads to the violation of the Clausius statement.

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FIGURE 5-34A perpetual-motion machinethat violates the first law ofthermodynamics (PMM1).

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FIGURE 5-43Execution of the Carnot cycle in a closed system.

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FIGURE 5-44P-V diagram of the Carnot cycle.

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FIGURE 5-45P-V diagram of the reversed Carnot cycle.

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FIGURE 5-46The Carnot principles.

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FIGURE 5-47Proof of the first Carnot principle.

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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.FIGURE 5-49The arrangement of heat engines used to develop the thermodynamic temperature scale.

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FIGURE 5-55The fraction of heat that can be converted to work as a function of source temperature (for TL = 303 K).

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FIGURE 5-57No refrigerator can have a higher COP than a reversible refrigerator operating between the same temperature limits.

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FIGURE 5-63The condenser coils of a refrigerator must be cleaned periodically, and the airflow passages must not be blocked to maintain high performance.