Questions tagged [thermodynamics]
Covers the study of (primarily homogeneous) macroscopic systems from a heat/energy/entropy point of view. Consider also using the tag: [statistical-mechanics].
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Is there any form of energy that can't be reduced to either kinetic or potential energy? [duplicate]
If you talk of thermal energy, it is I guess just the kinetic energy of particles. Bond energy is the potential energy of a molecular configuration etc. Is there any kind of energy which is neither ...
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What are the ways to solve the problem of the negative heat capacity of black holes since the canonic approach gives a positive heat capacity
From one hand, it is known that the heat capacity of a black hole is negative: \begin{align} M=\frac{1}{8\pi T} \quad \to \quad C_v=\frac{\partial Q}{\partial T}=\frac{\partial M}{\partial T}=-\frac{1}...
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Van der Waals - Gibbs Free Energy versus Pressure diagram - Derivation and "Analytic Continuation" meaning
I am looking at how phase transition is described in R. H. Swendsen's book "An Introduction to Statistical Mechanics and Thermodynamics". This is not homework, just trying to tidy up for ...
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How cold would it “feel” floating in space in Earth’s orbit? What`s the “effective temperature”?
So, space is cold but there is very little particles to transfer heat away from you in near vacuum. At the same time, the Sun is able to heat the surface of the Earth to temperatures of 50+ degrees ...
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Calculating the equilibrium temperature of a bob and water system when energy can be lost to the surroundings via heat [closed]
Let's say we have an aluminium bob at X degrees Celsius, and we have a water container at Y degrees Celsius. I am assuming here that the initial temperature of the container and the surroundings is ...
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Could black hole core pressure eventually overcome gravitational trapping? [duplicate]
I'm curious about the internal dynamics of black holes. If we imagine that energy (in the form of matter, light, and heat) is continuously absorbed, could internal pressure theoretically reach a point ...
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Why does para-hydrogen’s rotational specific heat capacity peak?
As temperature increases, it is expected that more energy states become available. If that’s the case why do we see a negative slope where increasing temperature actually decreases the specific heat? ...
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How is perpetual motion impossible? [duplicate]
I often read and hear from physicists that perpetual motion isn't possible due to the second law of thermodynamics. However, this doesn't make sense to me. The law doesn't say that the entropy of an ...
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Purity of continously measured open quantum system
An open quantum system can be described by the Lindblad master equation. If one wants to describe an open system, which is continously measured, one can describe such a system using a stochastic ...
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Derivation regarding Gibbs free energy
I'm a beginner, learning things like entropy and gibbs free energy for the first time. I'm trying to derive the famous equation: $$ΔG=ΔH-TΔS$$ but it looks like I'm getting nowhere. I start by ...
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Does a moving body possess a greater temperature than when it is at rest? [duplicate]
Temperature depends on the average kinetic energy of the particles of the system. If a system is moving, it possesses kinetic energy, which means the particles also possess that kinetic energy due to ...
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Would a perpetual system be created if a sealed container full of water empties into a sealed half - empty container?
In this scenario, the full container is placed above the half-empty container. A line, such as a pipe or hose, runs from the bottom of the full container to the top of the half-empty container. ...
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Johnson-Nyquist Noise Meaning of "Bandwidth"
The formula for the rms voltage associated with a noisy resistor at temperature $T$ is given by \begin{equation} v_{rms} = \sqrt{4kT\Delta fR} \end{equation} where $\Delta f$ refers to bandwidth and ...
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Is the second law of thermodynamics broken when we look at it from another perspective? [closed]
From what I know the second law of thermodynamics states that entropy in a closed isolated system must increase. From entropy increasing what I understand is microstates increasing . Now imagine this: ...
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Dark matter freeze-out in the Early Universe
Let us consider an Early Universe scenario in which I have dark matter particles (DM) $\chi_1$ and $\chi_2$, with a small mass splliting $\delta \ (m_2 = m_1 + \delta, \quad \delta \ll m_1, m_2)$, ...
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