The Effect of Increasing the Size of a Solid on Its Entropy

AI Thread Summary
Increasing the size of a solid body does not necessarily increase its entropy, particularly for rigid bodies, while deformable bodies may have different considerations. Enlarging a solid typically involves doing work and adding energy, which could affect entropy. If a body is expanded without a net energy change, its entropy could remain constant despite the increase in size. The discussion also touches on the distinction between adding more oscillators or increasing the distance between them, which can influence the overall entropy. Understanding these concepts requires a grasp of both classical and quantum mechanics.
LCSphysicist
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Does increase the size of the solid body increase its entropy? I was thinking about it using the Einstein model of solid.

S = k*lnΩ
Ω = (q+n-1)!/((q)!(n-1)!)

I am not sure how this question should be answer, i think if we talk about rigid bodies, the question don't even have sense, but about deformable bodies, technically increase its extension would not increase the entropy.
However, enlarge a body means to do work on it, that is, give it a additional energy.
Seeing by this way, if it would possible to enlarge a body and at the same time make it lost energy, in such way that the net energy change is zero, so we would end with a body/system greater than the one first, with the same entropy S = k*lnΩ.

Anyway maybe i am mixing quantum and classical mechanics in this topic, if this is the case, sorry, i don't know a lot quantum mechanics yet.
 
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LCSphysicist said:
Homework Statement:: All below
Relevant Equations:: All below

Does increase the size of the solid body increase its entropy? I was thinking about it using the Einstein model of solid.

S = k*lnΩ
Ω = (q+n-1)!/((q)!(n-1)!)

I am not sure how this question should be answer, i think if we talk about rigid bodies, the question don't even have sense, but about deformable bodies, technically increase its extension would not increase the entropy.
However, enlarge a body means to do work on it, that is, give it a additional energy.
Seeing by this way, if it would possible to enlarge a body and at the same time make it lost energy, in such way that the net energy change is zero, so we would end with a body/system greater than the one first, with the same entropy S = k*lnΩ.

Anyway maybe i am mixing quantum and classical mechanics in this topic, if this is the case, sorry, i don't know a lot quantum mechanics yet.
When you say you are increasing the size of the solid, are you adding oscillators/atoms (increasing N) or increasing the distance between oscillators/atoms?
 
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