Regarding efficiency of heat engines

AI Thread Summary
The discussion revolves around the calculation of engine efficiency using two different methods: one based on net work done and heat absorbed, and the other using the Carnot efficiency formula. The user reports discrepancies between the results obtained from these two approaches. Participants emphasize the importance of providing complete problem statements and using the Homework Template for clarity. There is a suggestion for the user to share their calculations to facilitate better assistance. The conversation highlights the need for thoroughness in problem-solving to avoid misunderstandings.
Nitin Gupta
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I tried to calculate the efficiency of a engine using the formula :
Efficiency = (Net Work Done) / (Heat absorbed)

And then I tried to calculate the efficiency of respective Carnot engine by two ways :
1) Efficiency = (Net Work Done) / (Heat absorbed)
2) Efficiency = 1 - (Temperature Lowest / Temperature Highest)

But the efficiency I am getting by the two methods different.How is this possible?
 
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Nitin Gupta said:
I tried to calculate the efficiency of a engine using the formula :
Efficiency = (Net Work Done) / (Heat absorbed)

And then I tried to calculate the efficiency of respective Carnot engine by two ways :
1) Efficiency = (Net Work Done) / (Heat absorbed)
2) Efficiency = 1 - (Temperature Lowest / Temperature Highest)

But the efficiency I am getting by the two methods different.How is this possible?

Beats me.

This is exactly why the PF Rules state that the Homework Template should be filled out completely, so that HW helpers don't have to extract information piece by piece from users.

Please use the HW template and post the complete problem statement you are working on along with your work which has led to an irreconcilable result.
 
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SteamKing said:
Beats me.

This is exactly why the PF Rules state that the Homework Template should be filled out completely, so that HW helpers don't have to extract information piece by piece from users.

Please use the HW template and post the complete problem statement you are working on along with your work which has led to an irreconcilable result.

Sorry for the extremely late reply...check this out...here is what I attempted...
 
Sorry, it looks like your work didn't make it into your post. :frown:
 

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