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Chapter 4: 4.12 (page 129)

Explain why a rectangular P V cycle, as considered in Problems 1.34 and 4.1, cannot be used (in reverse) for refrigeration.


Short Answer

Expert verified

The temperature range at which working substance absorbs heat must be less than the temperature range at which working substance rejects heat. As the rectangular PV cycle doesn't show this property, therefore it cannot be used for refrigeration.

Step by step solution

01

Given Information

The rectangular PV cycle.

Explain why it cannot be used (in reverse) for refrigeration.

02

; Explanation

A square PV cycle is shown as below.

The PV diagram is a closed loop. The area of the diagram represents the amount of work done during the process.

The temperature range at which working substance absorbs heat must be less than the temperature range at which working substance rejects heat.

As the rectangular PV cycle doesn't show this property, therefore it cannot be used for refrigeration.

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