All Questions
Tagged with reversibility adiabatic
16 questions
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How slow is a reversible adiabatic expansion of an ideal gas?
A truly reversible thermodynamic process needs to be infinitesimally displaced from equilibrium at all times and therefore takes infinite time to complete. However, if I execute the process slowly, I ...
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Principle of Caratheodory and The Second Law of Thermodynamics
Background
Constantin Carathéodory formulated thermodynamics on a purely mathematical axiomatic foundation. His statement of the second law is known as the Principle of Carathéodory, which may be ...
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How is this process not quasi-static yet reversible?
Consider a (adiabatic) canister with a piston containing some gas kept in a vacuum. There are two weights on the canister which equalize the pressure of the gas on the piston. Assume the system is at ...
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What is the difference between reversible and irreversible adiabatic expansion?
What is the difference between reversible and irreversible adiabatic expansion?
Is it true that the work done by the gas is the same but the pressure applied externally differ between two process?
If $...
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Examples of processes that are reversible isentropic but not adiabatic?
Since $ds=\frac{dq_{rev}}{T}$ for reversible processes it seems we can have reversible isentropic processes that are not adiabatic provided the temperature changes in such way that the sum of $\frac{...
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Are reversible adiabatic processes always isentropic?
If my understanding is correct, neither reversible nor adiabatic processes are necessarily isentropic.
But are reversible adiabatic processes always isentropic?
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Understanding the use of $d$ and $\partial$ in thermodynamics
It seems a hundred variations of this question have been asked, and it's difficult to find which of those questions relates to exactly what I'm asking. My apologies if exactly this question has ...
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Are there known conditions that ensure infinite slowness is reversible?
A system has a Hamiltonian that depends on a few external parameters $V,X_1,X_2...$.
$$H=H(V,X_1,X_2....).$$
We can assume the dependence is continuous enough. A process is in the limit of infinite ...
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On the way adiabatic processes were defined in Blundell's Concepts in Thermal Physics
In Blundell's Concepts in Thermal Physics, page $117$, the author defines an adiabatic expansion as follows,
The word adiathermal means ‘without flow of heat’. A system bounded by adiathermal walls ...
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Does "IF isentropic THEN reversible" only holds for adiabatic processes?
I know that: IF adiabatic and reversible THEN isentropic
First question: does the implication IF isentropic THEN reversible hold for adiabatic processes?
Second Question: if yes to the above, are ...
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Why doesn't reversible adiabatic expansion generate heat?
In analogy to a compressed gas allowed to reversibly expand and do work, I've been thinking about the behavior of a compressed spring that is very slowly and incrementally relieved of its pressure. ...
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Container divided by frictionless adiabatic wall: reversible or irreversible process?
I have encountered an issue in the following physical situation. Consider a rigid, thermally insulated container divided by a barrier parallel to its base into two parts, left and right, each ...
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Can two different points can be connected by multiple adiabatic curves?
I was watching this Thermodynamics lecture and I have a question on the 1st law. More exactly on how different adiabatic curves can connect the same initial and final states. See the diagram drawn at ...
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How can a reversible adiabatic expansion not increase entropy?
In the second stage of the Carnot cycle, a gas is thermally insulated and allowed to expand and do work on the piston.
I understand the reason people give is that because entropy is $\,dS = \,dQ/T$ ...
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What is quasi-static process?
What is the formal definition of quasi static process?
I am accustomed with it a bit intuitively, i want to know the formal definition of this. At some source I found the definition of somewhat ...
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Is a constant pressure adiabatic irreversible expansion possible?
We know that adiabatic law for an ideal gas is,
$$ PV^{\gamma} =C$$
the differential of this under constant pressure is,
$$ P \gamma V^{\gamma-1} dV = 0$$
Now, the pressure and volume can't be at all ...
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