Questions tagged [reversibility]
The potential for a thermodynamic process to be reversed in time. Alternatively, a quantification of how far an irreversible process is from being reversible, which relies on a comparison to a corresponding theoretical reversible process.
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Confusion regarding the equation $dS=\frac{\delta Q_{rev}}{T}$
In Reif's Fundamentals of Statistical and Thermal Physics he outlines a "proof" (sections 3.8 and 3.9) of the equation $dS=\frac{\delta Q}{T}$ for any quasi-static, infinitesimal process (i....
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Can ideal gas equation $PV = nRT$ be used in the intermediate stages of a irreversible and reversible process?
Suppose we have two processes, one is reversible and the other is irreversible. The ideal gas undergoes from state A to state B in both processes.
I want to know that can I apply the formula $PV = nRT$...
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Feasibility of entropy at zero temperature
I remember a college lecturer of mine once gave me this equation of entropy during one of his lectures on thermodynamics:
$$
\begin{align*}
\Delta{S} = \frac{ d {Q} }{T} \\
\end{align*}
$$
I found out ...
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Is the 2nd law a reason for the irreversibility of natural processes or a consequence of it?
I have been introduced to chemical engineering thermodynamics due to my academic background. I had learnt about internal energy, entropy etc and applied the equations to various scenarios of practical ...
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Entropy in irreversible adiabtic process
We know that,
$$dS=\dfrac{\delta Q_{rev}}{T}$$
If you have an irreversible adiabatic process between two thermodynamic equilibrium end states of a system, there exists no possible reversible adiabatic ...
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Use of Clausius theorem to prove entropy inequality in Fermi's Thermodynamics
At the beginning of Section 13 (at the bottom half of page 54 through the top half of page 55) of Enrico Fermi's classic Thermodynamics, he sets out to prove the relation (using his notation)
$$S(B) - ...
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What is the relationship between Clausius Inequality and 2nd Law?
I am confused about the application of the 2nd Law for reversible and irreversible processes and cycles.
I want to know how the Clausius principle, the Kelvin-Planck statement, and the Clausius ...
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What is the difference between a reversible process and an equilibrium? [closed]
I am confused about the differences between a reversible process and an equilibrium when considering their energy aspect.
Here is what I know so far.
(1) Equilibrium and Reversibility
Equilibrium ...
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Given a viably physical (isolated), quantum many body Hamiltonian, does an initial state of a superposition of energy eigenstates ever thermalize?
Given a viably physical, quantum many body Hamiltonian of a isolated system, if initially a state is prepared which is a superposition of energy eigenstates in an interval centered at E and E', not at ...
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Can equilibrium thermodynamics be used to analyze irreversible processes?
As usually taught in undergraduate courses, classical thermodynamics is actually thermo-statics, the thermal physics of equilibrium states. Even in this very restricted form it can and does make ...
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Is this a counterexample for the idea that reversible and quasi-static processes must infinitely slow?
Many people say that a reversible process must be quasi-static and infinitely slow. I (think I) understand the examples involving gases inside pistons to demonstrate the point, but I don't understand ...
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Is stochasticity totally incompatible with current theories of conservation of information in quantum physics?
Most physicists accept the unitarity principle of the universe, according to which the state of a system at any given time must determine its state at any other time (information is never lost, ...
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Distinguish a reversible process via measurements
Is it possible to distinguish between reversible and irreversible processes - say, the process of the working substance in a heat engine - via a measurement?
Its a bad question, in the sense that ...
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Change in entropy in reversible and irreversible process
Let's take a process with constant pressure in ideal gas for example. in reversible process
$dS=\int_{1}^{2}\frac{\delta Q_{rev}}{T}=\int_{1}^{2}\frac{C_pdT}{T}$
Assuming constant specific heat ...
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Clarification on the Use of $\frac{dS}{dE} = \frac{1}{T}$ vs. $\frac{dS}{dQ} = \frac{1}{T}$ in Thermodynamics
I'm currently studying thermodynamics and have encountered two expressions relating changes in entropy to temperature, but applied in seemingly different contexts:
$\frac{dS}{dE} = \frac{1}{T}$, ...
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