Questions tagged [adiabatic]
Thermodynamic processes that occur without exchanging heat between the system and its environment.
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What is the relation between the Adiabatic Approximation used in quantum chemistry and the one given in QM textbooks?
I am an aspiring quantum chemist and have come across two vastly different versions of the Adiabatic Approximation when studying Quantum Mechanics from the perspective of physics and chemistry ...
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Finding condition for Adiabaticity
I have a differential equation describing a resonator that looks like this:
$$ \frac{d\alpha(t)}{dt} = [j a - b]\alpha(t) + \sqrt b e^{jct}$$ where I can solve it putting: $$\alpha(t) = \alpha e^{jct}$...
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Why is an adiabat steeper than an isotherm in a $p$-$V$ curve?
What I have so far gathered is a mathematical explanation.
Since for an adiabatic process, $pV^γ=$ constant, for a unit change in pressure, change in volume would be very less. Therefore, if compared ...
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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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Temperature increase in fixed volume due to gas injection
I have a vessel of fixed volume with adiabatic boundary which is initially filled with air at pressure of 1 atm and temperature of 300 K. Now, I inject air from an external source at a fixed flow rate ...
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Change in temperature due to adiabatic expansion against the vacuum
Let's consider an ideal gas that expands in vacuum and it is thermally isolated from the surroundings. Since it is isolated, it does not exchange heat with the exterior $Q=0$. Since it is expanding ...
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In an adiabatic process, if there is no heat flow between system and surroundings, then why don't we consider temperature to be constant always?
How can the temperature of a body change unless heat flows in or out of it?
So shouldn't all adiabatic process be considered isothermal too? but that is not true as both the processes have different ...
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Question about Landau's derivation of the energy relation in Statistical Physics (Vol 5)
In Statistical Physics (Vol 5 of Landau's books) section 11, Landau derives an important relation: $\overline{\frac{\partial E(p, q;\lambda)}{\partial \lambda}} = \left(\frac{\partial E}{\partial \...
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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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Is sound really adiabatic because it is a fast process?
In many books I have consumed so far there is the statement that sound is adiabatic because heat transfer does not have nearly enough time to reach isothermal equilibrium. Doesn't this contradict ...
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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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How to model adiabatic lapse rate from first principles?
As a motivating example, consider that the grand canyon floor is ~11ºC warmer than the top. The dry adiabatic lapse rate of 9.8ºC/km, at the average depth of 1.2km deep, implies a 11.76ºC warmer floor ...
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Can we apply thermodynamics processes for real gas too? And how
Like in adiabatic process there is closed system but in reality we know there is no such thing as closed system there will be still exchange of heat so it will not work adiabatically means it is only ...
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Adiabatic expansion paradox [duplicate]
If we let a gas expand against vacuum with a piston which is not weightless then can we call it free expansion? If yes then there is a paradox . Work done by a gas is said to be = -p( external) ...
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