Thermodynamics and Entropy: Does an Atom's Energy Decrease Over Time?

AI Thread Summary
In the discussion, participants explore whether an engine operating between warm surface water and cold deep water in the tropics violates the second law of thermodynamics. It is clarified that as long as heat flows from the warmer reservoir to the colder one, there is no violation of the second law. The relationship to entropy is highlighted, noting that heat flowing from cold to hot would decrease entropy, which is not allowed in an isolated system. Additionally, a question arises about whether an atom's energy decreases over time due to entropy, prompting inquiries about atomic lifetimes. Overall, the conversation emphasizes the principles of thermodynamics and entropy in relation to energy transfer and atomic stability.
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Homework Statement



In the tropics, the water near the surface is warmer than the deep water. Would an engine operates between these two surfaces violates the second law? Why?

Homework Equations


Clausius statement:
Heat generally cannot flow spontaneously from a material at lower temperature to a material at higher temperature.

The Attempt at a Solution


I only knoe that the water near the surface is a high temperature reservoir and the deep water is a low temperature reservoir. Any engine only absorb heat at high temperature reservoir and do work and rejects heat at low temperature reservoir. I don't know what is the relationship of this with the second law. Thank you.
 
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I don't know what is the relationship of this with the second law.
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html"
 
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dlgoff said:
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html"

YES,...
But anybody can give me some hints or direction to tackle this question?
 
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Note that from the mathematical definition of entropy, a process in which heat flows from cold to hot has decreasing entropy. This can happen in a non-isolated system if entropy is created elsewhere, such that the total entropy is constant or increasing, as required by the second law.
http://en.wikipedia.org/wiki/Second_law_of_thermodynamics"
 
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cowcow8866 said:

Homework Statement



In the tropics, the water near the surface is warmer than the deep water. Would an engine operates between these two surfaces violates the second law? Why?

Homework Equations


Clausius statement:
Heat generally cannot flow spontaneously from a material at lower temperature to a material at higher temperature.

The Attempt at a Solution


I only knoe that the water near the surface is a high temperature reservoir and the deep water is a low temperature reservoir. Any engine only absorb heat at high temperature reservoir and do work and rejects heat at low temperature reservoir. I don't know what is the relationship of this with the second law. Thank you.
The answer is no. So long as heat flows from the warmer reservoir to the colder, there is no violation of the second law.

AM
 
I have had a simple question that has nagged me since my '60s era physics classes. Simply put, does an an atom's energy "run down" over time? e.g. Is it a constant or does it drop over time due to entropy? If it drops over time, what is the lifetime of an atom?
 
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