Heat Engine - Maximum Efficiency

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The maximum efficiency of a heat engine operating between two temperature reservoirs can be calculated using the Carnot efficiency formula, which involves absolute temperatures. The temperatures must be converted to Kelvin for accurate calculations. The formula for maximum efficiency is e = 1 - (Tc/Th), where Tc is the cold reservoir temperature and Th is the hot reservoir temperature. In this case, the temperatures are 25 degrees Celsius (298 K) and 375 degrees Celsius (648 K). The discussion emphasizes the importance of using absolute temperatures rather than heat flow ratios for determining efficiency.
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Homework Statement


A heat engine operates between a reservoir at 25 degrees Celsius and one at 375 degrees Celsius. What is the maximum efficiency possible for this engine?


Homework Equations



e = \frac{Q<sub>c</sub>}{Q<sub>h</sub>}


The Attempt at a Solution



I'm afraid that the equation above requires units in Joules to calculate thermal efficiency. Is there an equation adapted for this situation? Or does this require more figuring?
 
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Just a little more figuring ;) think of the Carnot cycle ;)
 
Check your textbook for another efficiency equation, one involving absolute temperatures rather than Q's.
 
science.girl said:

Homework Statement


A heat engine operates between a reservoir at 25 degrees Celsius and one at 375 degrees Celsius. What is the maximum efficiency possible for this engine?

Homework Equations



e = \frac{Q<sub>c</sub>}{Q<sub>h</sub>}
Efficiency is the ratio of Energy (work) out to Energy (heat flow) in. This is not Qc/Qh

AM
 

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