Questions tagged [equilibrium]
Equilibrium is the condition of a system in which all competing influences are balanced. These can range from forces (static/dynamic equilibrium), to chemical processes (chemical equilibrium) and temperature gradients (thermal equilibrium).
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Why do we say that at boiling point liquid and vapour exist in equilibrium?
I understand that at boiling point, vapour pressure becomes equal to the external pressure. But in my textbook it is written that at boiling point liquid and vapour exist in equilibrium. What does it ...
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What are some good articles on trend to equilibrium?
I am interested in studying systems out of equilibrium that are trending to equilibrium. Trend to equilibrium, entropy production, etc. seem to be very tricky topics. Any suggestions will be ...
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A paradox while explaining the equilibrium of books
An even number of books (say four) are held in the manner shown in the figure. It is obvious that if we apply a large force inwards, we can increase the normal force, and hence the friction which ...
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Demonstration that electric current at equilibrium is zero in crystals
As it is well known, electrons at equilibrium (no external field) do not conduct electric current, i.e.
$\int_{BZ} dk\,v_{k}\,f(\epsilon_k)=0$
where $f(\epsilon_k)$ is the Fermi-Dirac distribution
$...
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Equilibrium in physics
We know that harmonic oscillator or pendulum will not reach a equilibrium at infinite time. But why a system of gas molecules reaches equilibrium (entropy of an isolated system will tend to increase ...
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Two interacting blackbodies (one inside another) - when will thermal equilibrium be attained? [closed]
As I understand it, an ideal blackbody absorbs (and subsequently starts emitting) all incoming radiation. In typical setups like determining a planet's temperature given its albedo and distance from a ...
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Statics problem from classical mechanics
I was solving David Morin's book on classical mechanics.
In the solution for the second part of the "a" part of the question, why is the normal force defined as $Ndθ$ and not just $N$? Is ...
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Equilibrium of a system of charges
Suppose three positively charged particles are constrained to move on a fixed circular track. If the charges were all equal, an equilibrium arrangement would obviously be a symmetrical one with the ...
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If the net external moment on a body about a point is zero
I was told that
If net external moment of some forces is zero about a point, then the net external force passes through the point.
I know it's not true in general, what was the special condition ...
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If three forces act on an object in equilibrium, they must pass through a common point. How does this generalise?
If three forces act on an object in rotational equilibrium, the line of action of each force must pass through a common point (parallel forces satisfy this as they go through a common point at ...
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Thermodynamic work and potential functions
I was reading about the maximum thermodynamic work of a system (Z) that is going to equilibrium.
\begin{equation}
dZ = dU + p_0 + T_0dS
\end{equation}
I then came across the thermodynamic potential ...
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Intuition for imaginary time Greens function
I understand that $$G^M(0,0^+) = \operatorname{tr}\{\rho O_2 O_1\}$$ (I am not putting hats on the operators here because they don't render in the correct position) is simply the expectation value of ...
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Calculate equilibrium position using conservation of energy in vertical spring mass system
I am very confused in the vertical spring mass system right now, below is some of my thinking process:
Say I want to find the equilibrium of a spring mass system, my teacher used the force way to ...
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How does this tensegrity table work?
I have assembled below a desk toy which seems to defy laws of physics at first glance (objects can be placed on top of it up to a certain limit, since it is already under strain).
The toy is in fact ...
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How are the Lagrange points determined?
According to Hyper Physics, there are 5 equilibrium, or Lagrange points of the Earth-Moon system and only 2 of them are said to represent stable equilibrium points.
This made me think if there is an ...
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