How Do You Calculate Efficiency and Work in the Carnot Cycle Using a TS Diagram?

AI Thread Summary
The discussion focuses on calculating efficiency and work in the Carnot cycle using TS diagrams. For figure A, the heat inputs and outputs are expressed as Qh=T1Δs and Qc=(T1-T2)Δs, leading to an efficiency of η=T2/T1. In figure B, the calculations yield Qh=(T2-T1)Δs and Qc=-T2Δs, resulting in η=(2T2-T1)/(T2-T1), which is questioned for accuracy. The conversation emphasizes the relationship between work (W) and heat (Qh) in terms of the areas under the graphs, prompting a comparison of figures A and B regarding W and Qh. Understanding these relationships is crucial for accurately determining efficiency in the Carnot cycle.
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Homework Statement



Part B

Homework Equations



Thermodynamics, Carnot cycle, ts diagram

The Attempt at a Solution



I understand that for figure A, Qh=T1Δs and Qc=(T1-T2)Δs once you take the negative out of the Δs. For figure B, Qh=(T2-T1)Δs and Qc=-T2Δs once you take the negative out of the Δs. For the efficiency of figure A, I got η=T2/T1 after plugging into 1-Qc/Qh. For figure B, I got η=(2T2-T1)/(T2-T1). I have a feeling that what I have for figure A is right but that B is no where close. Any help would be awesome
 

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Keep in mind that efficiency is given by:

η = W/Qh

and W = Qh-Qc.

What is W and Qh in terms of the areas under these graphs? Hint: What is the area under a sloping line?

Is there a difference between A and B in terms of W? How about in terms of Qh?

AM
 
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