Questions tagged [adiabatic]

Thermodynamic processes that occur without exchanging heat between the system and its environment.

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How can mechanical equilibrium be guaranteed in adiabatic expansion? [closed]

Assuming I have a perfectly thermally insulated metal piston in my hand. I reach for the piston, pull on it and let go again- nothing moves. What happened to the gas in my system: T down, p down, V up....
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Why does adiabatic expansion occur in the carnot process?

(Spoiler: Why adiabatic expansion happens in Carnot cycle doesn't really answer the question for me.) In the Carno cycle, the open system is first brought into contact with the warm reservoir, which ...
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Calculating the required volume of Helium to put in a weather balloon [closed]

Question I am working on a project where we will launch a weather balloon with some scientific instruments tied beneath the balloon. We fill the balloon with helium from tanks of compressed helium. ...
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Adiabatic expansion on ideal gas [closed]

Please help in this exams question. In an adiabatic expansion of ideal gas PV^gamma is a constant .show also that TV^gamma-1/gamma is also a constant
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How to derive $ TV^{1-\gamma}$? I get $ \frac{T}{V^{1-\gamma}}$ [closed]

For an adiabatic process we have $dQ=0$, thus the first law gives: \begin{align} \mathrm{d}E &= \mathrm{d}W, \\ nC_V \mathrm{d}T &= - P\mathrm{d}V = - \frac{nRT}{V} \mathrm{d}V, \\ \frac{\...
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Doubts regarding work and pressure during adiabatic compression of a gas in a cylinder

So, I have doubts regarding the work done on the gas in this situation: Let's say I have an ideal gas inside an adiabatic cylinder fitted with a piston of area $A$. The piston has mass $M$. Outside ...
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What is symmetry in this context?

I'm reading a paper that was written by a senior undergraduate at my college and I'm having a trouble trying to understand a part of his paper. His paper is on Measuring nonlinear Phase accumulation ...
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Is vapor pressure conserved during an adiabatic ascent of an air parcel?

Consider an air parcel with relative humidity $H$ and vapor pressure $e$ that experiments an adiabatic lifting process. Obviously the saturating vapor pressure is going to change since said process is ...
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An ideal gas expands into vacuum in an insulated rigid vessel. Which of the followings happens? [closed]

This question came in the Dhaka university admission exam 2018-19. An ideal gas expands into vacuum in an insulated rigid vessel. Which of the following happens? A. no change of internal energy B. a ...
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Can a small amount of super-compressed gas cause much cooling upon rapid expansion and contact? [closed]

Generally, a small amount of mass in the range of $0.001$ - $0.01$ kg, even if chilled to tens of degrees below absolute zero in a hypothetical case to test extremes, even with 5000 specific heat and ...
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Radial dependence of temperature for adiabatic expansion of ideal gas

If the solar wind propagates out adiabatically with a constant speed and can be regarded as an ideal gas, how the solar wind temperature depend on radial distance from the sun $r$, i.e. $T$ as a ...
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Why do internal combustion engines use adiabatic expansion and combustion?

In the gasoline engine, the gasoline mixture is heated at constant volume, followed by adiabatic expansion. In the diesel engine, the mixture is heated at constant pressure, and this is followed by ...
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Finding equation of internal energy in adiabatic process

I am doing a review of thermodynamic and I encounter the following question, Show that if a single-component system is such that $PV^k$ is constant in an adiabatic process (k is a positive constant) ...
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What is the type of system, if I have an opened container with hot water inside, but no heat input to the system?

I have a school project, where I am trying to generate electricity using TEG modules that are attached to an aluminium container that contains hot water. The container is opened and there is no heat ...
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Adiabatic expansion of the universe

I was wondering why we consider the universe to expand adiabatically. If the universe is a closed system shouldn't be the energy conserved? Does the adiabatic expansion change the total internal ...
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Instantaneous eigenstate and time dependent Schrodinger equation

Instantaneous eigenstate $\psi(t)$ is defined as $\hat H(t)\psi(t)=E(t)\psi(t)\tag{1}$ But in the lecture notes of Quantum Physics III MIT (in the section of adiabatic approximation), it is written ...
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Why doesn't temperature decrease with an increase of volume in the syringe?

I made an experiment using a closed syringe with the volume marks. At the beginning, the piston is at $5\rm\, ml$, then I move it to $20\rm\, ml$. Since the change is approximately adiabatic, we can ...
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Derivation of astrophysical entropy

The definition of entropy in astrophysics is often actually just the adiabatic constant $K$ relating $P=K\rho^\gamma$ where $\gamma$ is the usual adiabatic index, $P$ is the pressure and $\rho$ is the ...
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Rabi oscillations within the adiabatic theorem?

I'm studying Rabi oscillations in a two-level system (TLS) with Hamiltonian \begin{align}H(t)=\omega_0 \sigma_z + \Omega \cos(\omega_1 t) \sigma_x.\end{align} The model is usually treated within the ...
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Question regarding adiabatic process (Ex 12.2 in Blundell's Concepts in Thermal Physics)

It can be derived from first law of thermodynamics that $$dQ=\bigg(\frac{\partial U}{\partial T}\bigg)_V dT +\bigg[\bigg(\frac{\partial U}{\partial V}\bigg)_T+p\bigg]dV$$ On page 119 of the book, a ...
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Is adiabatic work extensive?

The First Law of Thermodynamics for an adiabatic process is: $\Delta U=W$. The internal energy is extensive. Thermodynamic work is neither extensive nor intensive in general, but is it extensive, if ...
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What is the adiabatic temperature gradient of ice?

What is the adiabatic temperature gradient of ice at Earth's surface conditions? The adiabatic temperature gradient is a non-conductive spatial temperature difference caused by acceleration on thermal ...
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"Classical" adiabatic approximation: please help me understand better

In this1 paper they use an adiabatic approximation to reduce two differential equations to one. Could you please recommend some alternative reading for this (semi) classical adiabatic approximation, ...
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Uniqueness of Irreversible and adiabatic processes in finite time

Let the external intensive and extensive "mechanical" variables be denoted by $Y_k, X_k$. These variables are well defined irrespective of the system is in equilibrium or not. For an ...
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Can adiabatic heat exchange between different temperatures ever be reversible?

I've been told, A volume 2X of Temperature 0.5*(T1+T2) is always at higher entropy than thermally insulated volumes, 'X' at T1, 'X' at T2 put together. Let's take Sys1 (A volume 2X of Temperature 0.5*(...
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What steps are exact in Born-Oppenheimer and adiabatic approximation?

I am reading about adiabatic and Born-Oppenheimer approximation and I can't understand what steps are exact and what steps are approximations. Both these approximations are based on the idea that as ...
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Adiabatic sound speed in static spherically-symmetric perfect-fluid solutions (SSSPF) of Einstein field equations (EFE)

Why $\sqrt{dp/d\rho}$ is interpreted in SSSPF solutions as adiabatic speed of sound although the corresponding equations are static? In static world all times derivatives are zero and without wave ...
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Why adiabatic expansion happens in Carnot cycle

$A \rightarrow B$: Isothermal expansion happens. Since the internal energy purely depends on the temperature ($E_{int} = knRT$, $k = \frac{3}{2},\frac{5}{2},3$), then $\Delta E_{int}=0$ in an ...
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Why the irreversible work carried in an adiabatic condition never causes change in internal energy?

I saw the lecture of thermodynamics on the MIT opencourse ware . In that lecture , the professor said that change in internal energy in an adiabtic process is caused by only reversible work , and not ...
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Role of Berry's curvature in nanomaterials

what is the physics behind Berry's curvature? In many papers, they are explaining topological and anomalous quantum hall effects via Berry's curvature. but what is the physics behind this curvature ...
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Normal Shockwaves and its Thermodynamics

Please read this page before going to my question. When we derive the relation between Mach no. to the left side of the shock wave (M1) and that to the right side of the shock wave (M2),we do that ...
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Adiabatic turn-on of free multi-particle states

Consider a second-quantized operator $\mathcal{H}_{full}$ describing some interacting QFT, whose action is known on a set of Fock states $\{\mathcal{|F\rangle}\}$, which, in turn, are the eigenstates ...
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Why is air considered to rise adiabatically?

Do air parcels not push against other air and do work on them? When air molecules within an air parcel bump into air molecules outside the air parcel do they not transfer energy to them?
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Adiabatic temperature increase given work done on (ideal) gas

I'm playing around with a Euler's method simulation of an adiabatic compression/decompression process on an ideal gas. If I have a volume of gas and I contract its volume slightly, I will be doing ...
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Is this set up a reversible process and is the adiabatic equation of state applicable here?

I had this question in a recent test: My teacher while discussing this question used the adiabatic equation of state PV^gamma=constant to solve for length L (options C and D). And used work energy ...
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In adiabatic condition, how can i find ground state through time evolution operator?

decompose the evolution operator into a sequence of steps using the Trotter-Suzuki formula unitary operator is the evolution operator from 0 to $T $, $k$ is a large integer so that $τ = T /k$ is a ...
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Adiabatic Invariance and Magnetic Moment

In plasma physics, particularly, in magnetic mirrors, we have a very well-known result, which is the invariance of the magnetic moment of the particles trapped in the mirror. I've saw in some notes ...
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Why does an elasticity approach for an adiabatically compressed bubble give a different answer?

Problem (inspired by this question): a bubble of ideal gas at pressure $P_0$ and volume $V_0$ is adiabatically compressed to conditions $P_1, V_1$ such that its radius $r$ is reduced by $a$, where $a\...
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Why is $c_p/c_v$ term introduced in adiabatic process?

In an adiabatic process we know there is no change in enthalpy or basically enthalpy change is zero. which means any external work done the internal energy does equal opposite work so as to keep $dH=0$...
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Work done on system and surroundings in an irreversible adiabatic compression

In an adiabatic irreversible compression process, suppose the pressure $P_{ext}$ compresses the piston and does some work say 50J. (50J of energy is lost by surrounding). Since the pressure $P_{int}$ ...
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Reversible adiabatic process insight

How can a reversible adiabatic process (theoretically) be brought about since the system is insulated? A $\mathrm dP$ change in pressure will lead to a $\mathrm dT$ change in temperature thus ...
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On Adiabatic approximation

In Sakruari's Modern Physics, it's written that $$H(t)|n;t\rangle =E_n(t)|n;t\rangle $$ simply noting that at any particular time $t$, the states, and eigenvalues may change. If we now look for ...
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Adiabatic evolution of Landau quasiparticles

In the Landau Fermi-liquid theory there is the standard argument that if we initially started from the independent electron picture and turned on the interactions adiabatically, then we would end up ...
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Adiabatic evolution of superposition of states

I am supposed to find a specific superposition of eigenstates of a time-dependent hamiltonian $H(t)$. The hamiltonian is of the form : $H(t) =\sum_i \left(J\vec{\sigma}_i\cdot \vec{\sigma}_{i+1} + h(t)...
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Doubt related closed system and isolated system

In my book it is written that "A closed system with all adiabatic boundaries may not be isolated system." But I have my own doubts. If closed system then no exchange of mass or material is ...
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Free Expansion in Szilard Engine?

A crucial step in the definition of Szilard Engine is computing the work done by the single molecule in moving the piston from the middle to one end (left or right, depending on the location of the ...
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Adiabatic approximation

The celebrated adiabatic theorem states that for a system initially in the eigenstate $|\psi(0)\rangle = |n(0)\rangle$ for $t=0$, it will stay in that state afterward under adiabatic evolution: $$ |\...
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All three thermodynamic terms being variable

In preliminary thermodynamics, I learned about 4 special cases where at least one thermodynamic term is constant like isobaric, adiabatic, isochoric process. But how to evaluate the work, change in ...
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Is it always true that a non-adiabatic reversible process is an isothermal process?

In a Carnot Cycle, a reversible isothermal process is a non-adiabatic reversible process. Is it always true that a non-adiabatic reversible process is an isothermal process?
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Can adiabatic processes decrease entropy (the Second Law as defined in Reif)?

In Chapter 3.11 of the book "Fundamentals of Statistical and Thermal Physics" by F. Reif, the following is given as a definition of the Second Law of Thermodynamics: In any process in which ...
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