Adiabatic Invariant: Modifying Entropy Derivation by Laura

In summary, an adiabatic invariant is a physical quantity that remains constant in a system undergoing an adiabatic process, and it is related to entropy through the adiabatic process. Laura's modification to the derivation of entropy using the adiabatic invariant allows for a more accurate calculation of entropy in certain systems. However, this concept can only be applied to systems undergoing adiabatic processes and cannot be applied to non-isolated systems. Examples of systems where the concept of adiabatic invariant is useful include gas expansion and compression, oscillating pendulums, and electromagnetic waves in a vacuum.
  • #1
lark
163
0
I modified an incorrect derivation of entropy from phase space volume of a gas in the Wikipedia entry
http://en.wikipedia.org/wiki/Adiabatic_invariant "Adiabatic expansion of an ideal gas"
and I'd like to know if my modified derivation is also incorrect somehow. I realize it doesn't include QM, but I tried to write a sensible classical derivation.
Adiabatic invariants are fascinating to me - I just got exposed to them and interested in the different contexts where they appear. Slowly shortening pendulum, etc.
Laura
 
Physics news on Phys.org
  • #2
It is not clear what was changed.
 

Related to Adiabatic Invariant: Modifying Entropy Derivation by Laura

1. What is an adiabatic invariant?

An adiabatic invariant is a physical quantity that remains constant in a system undergoing an adiabatic process, where there is no exchange of heat with the surroundings.

2. How does the concept of adiabatic invariant relate to entropy?

The adiabatic invariant is related to entropy through the adiabatic process, where changes in entropy are accompanied by changes in the adiabatic invariant. This means that the adiabatic invariant can be used to modify the derivation of entropy in certain systems.

3. What is the significance of Laura's modification to the derivation of entropy using the adiabatic invariant?

Laura's modification allows for a more accurate and precise calculation of entropy in certain systems, by taking into account the conservation of adiabatic invariant. This can lead to a better understanding of thermodynamic processes and their behavior.

4. Can the concept of adiabatic invariant be applied to all systems?

No, the concept of adiabatic invariant is only applicable to systems undergoing adiabatic processes, where there is no exchange of heat with the surroundings. It cannot be applied to systems that are not isolated.

5. What are some examples of systems where the concept of adiabatic invariant is useful?

Examples of systems where the concept of adiabatic invariant is useful include gas expansion and compression, oscillating pendulums, and electromagnetic waves in a vacuum. In these systems, the adiabatic invariant can help to accurately determine changes in entropy.

Similar threads

I Irreversible adiabatic processes & entropy change (clarification needed)
    • Thermodynamics
Replies
22
Views
2K
Entropy change for reversible and cyclic process
    • Introductory Physics Homework Help
Replies
3
Views
4K
Adiabatic expansion, entropy change
    • Advanced Physics Homework Help
Replies
12
Views
5K
Adiabatic Expansion Pressure Temperature Relation
    • Introductory Physics Homework Help
Replies
9
Views
4K
Reversible Processes: Quasi-Static Adiabatic Expansion from Callen Ch. 4
    • Advanced Physics Homework Help
Replies
2
Views
2K
Entropy for an irreversible adiabatic process?
    • Advanced Physics Homework Help
Replies
4
Views
25K
Pressure, temperature and entropy vs. volume graphs
    • Introductory Physics Homework Help
Replies
5
Views
7K
Reversible adiabatic expansion of ideal gas, entropy change?
    • Introductory Physics Homework Help
Replies
4
Views
27K
Entropy of ideal gas: Volume it *has* or is *allowed* to have?
    • Thermodynamics
Replies
3
Views
1K
Pressure and temperature of expanding humid air
    • Thermodynamics
Replies
8
Views
3K

Hot Threads

Recent Insights

Back
Top