All Questions
Tagged with adiabatic reversibility
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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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Why do we need an adiabatic expansion in the Carnot cycle? [duplicate]
As we know that 1st process is an reversible isothermal expansion during this the system is in quasi static equilibrium which helps in increasing the volume of the system but why does the second step ...
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Container divided by adiabatic wall with mass and friction: why is it a quasi-static process?
Thanks to the help of @ChetMiller, the following fact is essentially concluded in this thread. Consider a rigid, thermally isolated container divided by a massless barrier parallel to its base into ...
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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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2
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Reversibility of the ideal Carnot cycle
How do adiabatic processes in the reversible Carnot cycle take place? Is the gas adiabatically isolated? If so, how would that happen in real life? (I know that Carnot cycle is not practically ...
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The work and reversibility of an adiabadically stretched band
I currently working on this. More specifically I have a question about Problem 2.8 (solution on page 34 and exercise on page 25 of the pdf). I have 4 questions
1.
In the solution for b) the author ...
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Is there an equivalent of "adiabatic" for work (i.e. a workless transformation)?
In Fermi's Thermodynamics (1937), Chapter I, §1, he defines an isochore transformation as
a transformation during which the system performs no external work
He then discusses the case where the ...
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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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Derive $ΔS = Nk\ln(V/V_0)$ using fundamental equations of thermodynamics [closed]
I am considering a system with an ideal gas undergoing an adiabatic expansion. The initial volume is $V_0$ and final is $V$.
From this, How do I derive $\Delta S = Nk\ln(V/V_0)$ using fundamental ...
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Why can't a heat engine have 100% efficiency?
Using the idea of isotherms and adiabats, I came up with the following argument to convince myself. First imagine the working gas within the system being heated along an isochore (hence all heat ...
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Why is the final temperature of irreversible adiabatic processes higher than that of reversible adiabatic processes?
Suppose an irreversible adiabatic expansion process and a reversible adiabatic expansion process are starting from the same initial state, say, P1V1. Now, let both of these processes have equal ...
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Understanding page 141 of Blundell’s Concepts in thermal physics
On this page (in the second edition), there is a figure containing two states A and B of a system:
There are two paths between A and B: one is an irreversible change, and the other is a reversible ...
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Why isn't the free expansion of a gas in an adiabatic container isentropic?
If you expand a gas adiabatically using a piston, the process is isentropic. However, if you simply remove the piston and let the gas expand freely, the process is now not isentropic. What makes these ...
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Proof of Caratheodory's theorem
Caratheodory's formulation of second law of thermodynamics, also referred to as Caratheodory's principle states
In any neighbourhood of any thermodynamic state $P$ there exist states which are ...
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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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