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Chapter 21: Q. 5 (page 593)

Rank in order, from largest to smallest, the thermal efficiencies η1to η4of the four heat engines in FIGURE Q21.5. Explain.

Short Answer

Expert verified

Rank in order from largest to smallestη3>η2=η1>η4

Step by step solution

01

Step :1 Introduction 

The Carnot engine is the most efficient of any heat engine that operates between two temperatures.

Heat pumps take heat from a cold place and transport it to a warmer one in the opposite direction of spontaneous heat transfer; nevertheless, a refrigerator is a piece of household equipment that is kept at a lower temperature than the outside air.

02

Step :2 Explanation 

Useη=Wout/Qinto get ,

η1=0.4η2=0.4

η3=0.6η4=0.06

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