Thermodynamics of a Heat Engine - (First/Second Law)

AI Thread Summary
The discussion revolves around the thermodynamic principles governing heat engines, specifically addressing why two bodies in a problem are at the same temperature. Participants explore the implications of having three bodies at different temperatures, suggesting that this scenario allows for the continuous heating of the hottest body. The use of a Carnot engine is highlighted as a method to increase temperature through work. The conversation emphasizes the importance of temperature differentials in thermodynamic processes. Understanding these principles is crucial for analyzing heat engines effectively.
laser1
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I am not sure why two of the bodies are at the same temperature to end with. I am pretty certain that they don't have to be - but the author of the problem set it this way for some reason I'm missing (my guess). My reasoning: Put 100 K and 300 K together for a short time, but not so long that they have the same temperature. Voila! All three bodies have different temperatures. Thanks
 
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laser1 said:
I am not sure why two of the bodies are at the same temperature to end with.
Hint: Suppose all three bodies have different temperatures. Can you see how it would always be possible to raise the temperature of the hottest of the three?
 
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TSny said:
Hint: Suppose all three bodies have different temperatures. Can you see how it would always be possible to raise the temperature of the hottest of the three?
Ah yeah fair because you could always increase it by using a Carnot engine and raise the temp. due to work! Thanks
 

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