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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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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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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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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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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Why must solids in equilibrium become crystalline?
In Landau's Statistical Physics's analysis of solids, he begins with the remark that solids are caracterized by their atoms' small oscillations about equilibrium positions. However, he states that ...
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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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An object is connected to the end of a spring and is immersed in water. What are the forces acting on the object? [closed]
The actual question is
A copper piece of mass 10g is suspended by a vertical spring. The spring elongates 1 cm over it's natural length to keep the piece in equilibrium. A beaker containing water is ...
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What is the difference between a reversible process and an equilibrium? [closed]
I am confused about the differences between a reversible process and an equilibrium when considering their energy aspect.
Here is what I know so far.
(1) Equilibrium and Reversibility
Equilibrium ...
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Serway & Jewett's definition of rotational equilibrium
On p. 364 of Physics for Scientists and Engineers (9th ed.), Serway and Jewett define a rigid object to be in rotational equilibrium if it has an angular acceleration of zero. They then state that a ...
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How do differently colored objects reach the same temperature if they are completely isolated together?
Imagine a perfectly reflective container, filled with vacuum and two bodies with different colors, i.e. they have different emissive and absorptive properties. The bodies don't touch each other or the ...
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Pressure difference between a box and the outside atmosphere
Say I have a box of volume $V$, with an ideal gas inside it with temperature $T_b$. I don't know the number of particles inside it. The box is surrounded by the room's environment, which has ...
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Investigating the stability of a wooden block
Consider the above experimental design. At the end of the strip, at point $p$, a mass $m$ is attached, the stability of the wooden block above is determined by the angle $θ$ at which the block topples ...
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Apparent inconsistency with Maxwell-Boltzmann energy distribution
The Maxwell-Boltzmann distribution for the kinetic energies of particles is given as ( https://en.wikipedia.org/wiki/Maxwell%E2%80%93Boltzmann_distribution#Distribution_for_the_energy )
$$f(E) = 2 \...