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

In summary: If you are adding oscillators/atoms, then the entropy would increase, as S = k*lnN. If you are increasing the distance between oscillators/atoms, then the entropy would not increase, as S = k*lnΩ.
  • #1
LCSphysicist
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Homework Statement
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Relevant Equations
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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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  • #2
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?
 

1. What is entropy in solid bodies?

Entropy in solid bodies refers to the measure of the amount of disorder or randomness in the arrangement of particles within a solid material. It is a thermodynamic property that describes the distribution of energy within a system.

2. How does entropy affect solid bodies?

Entropy affects solid bodies by determining the stability and behavior of the material. As entropy increases, the particles within the solid become more disordered, leading to changes in physical properties such as melting point, thermal conductivity, and elasticity.

3. Can entropy be reversed in solid bodies?

No, entropy cannot be reversed in solid bodies. According to the second law of thermodynamics, the total entropy of a closed system will always increase over time. While it is possible to decrease the entropy of a specific region within a solid, the overall entropy of the system will still increase.

4. How is entropy calculated in solid bodies?

The entropy of a solid body can be calculated using the formula S = k ln W, where S is the entropy, k is the Boltzmann constant, and W is the number of microstates (possible arrangements) of the particles within the solid. The higher the number of microstates, the greater the entropy of the solid.

5. What factors can affect the entropy of solid bodies?

The entropy of solid bodies can be affected by several factors, including temperature, pressure, and the composition and structure of the material. Changes in these factors can lead to changes in the arrangement of particles and thus affect the overall entropy of the solid.

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