I Work done in cycle of a refrigerator (in Heat and Thermodynamics by Zemansky)

Thread starter MatinSAR
Start date Jan 27, 2024
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Heat problem Thermodynamics

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In the discussion on the work done in the cycle of a refrigerator, it is clarified that the initial assumption is incorrect. The relationship between heat absorbed from the hot reservoir (Q_H) and heat expelled to the cold reservoir (Q_L) indicates that Q_H is greater than Q_L. Consequently, the difference |Q_L| - |Q_H| results in a negative value, which cannot equal the work done (|W|). This confirms the understanding that the work done in a refrigeration cycle must align with the thermodynamic principles outlined in Zemansky's text. The conclusion affirms the correctness of this interpretation.

Jan 27, 2024

MatinSAR

TL;DR: I caanot understand what is happnening in chapter 6 part 7. The book has two equations for work done in cycle of a refrigerator

I guess the first one is wrong.
Because in this cycle we have ##|Q_H| > |Q_L|## then ## |Q_L| - |Q_H| ## is negative and caanot be equal with ##|W|##.

Am I right?

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Jan 27, 2024

vela

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Yes.

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