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If you have a glass of water, every molecule of water is under the influence of the gravitational potential field. Each molecule pushes down on the molecules below. The molecules of water near the bottom of the glass experience the downward force from all molecules above them (each molecule transfers the force downward). If you made a hole near the bottom of ...


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I will not answer your question directly; only give you some tools that should help you answer the question (in practice) yourself. To focus the attention, find below a typical heating/cooling diagram for a frozen pure substance. The vertical axis marked $T$ represents temperature (in degrees Celsius). Three significant temperatures are indicated on the ...


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A recent work that uses nanothermodynamics and includes a computational investigation of the kind you are asking about for an Ising lattice: R.V. Chamberlin, The Big World of Nanothermodynamics Sec.5 of the following paper makes a reference to another paper that appears to have tested the limits of usual thermodynamics in single polymer stretching ...


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It is always true that, for an ideal gas, $\Delta U = C_V \Delta T$, regardless of the process. Remeber, we define $C_V=(\delta Q/dT)_V$. Since this is happening at constant volume (aka $\delta W=0$), we have $C_V=(\delta Q/dT)_V=(dU/dT)_V$. Then, since $U$ doesn't depend on volume for an ideal gas, we have that $C_V=dU/dT$ even if volume is changing. So ...


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The Maximum Entropy principle, principally popularized by Jaynes, is known by most people having studied statistical physics. The way I see it, although Jaynes considered it as crucial in the foundations of equilibrium statistical mechanics and other people in the field still do (like Roger Balian for instance), it is more taught and thought of as a useful ...


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Part of your problem comes from thinking that the potential energy is somehow located in or a property of the person alone. And the way the subject is usually introduced could easily lead you to think that, but it's not right. The potential energy is a property of the person-Earth system. In fact all potential energies are properties of systems of ...


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To start with the law of increasing entropy applies to isolated systems. The system you describe is isolated if one considers the total entropy of both the paramagnetic material and the permanent magnet, including any radiation. The order introduced in the paramagnetic material is balanced by a disorder in the permanent magnet plus any radiation from ...


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A cooler that has ice and water in it will be held at 32 degrees Fahrenheit until all the ice is melted. The rate at which the ice melts depends on the rate at which heat can enter the container. The rate at which heat crosses any thermal boundary can be modeled as: $$\dot Q=\frac{\Delta T}{\sum 1/h_i}$$ Where $h_i$ represent the thermal conductivity of ...


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I haven't given this enough thought yet, but at a first glance, I would say no, a potential having $\mu, V, E$ as natural variables would not be a valid one. One possible attempt to obtain such a thermodynamic potential $Q$ that is a natural function of $\mu,V,E$, would be a Legendre transform of the entropy $S(E,V,N).$ We have: \begin{align} dS = ...


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A force does not require a constant input of energy to exist. Energy is only required to perform work, which is exerting a force over a distance. $$ W = \mathbf F \centerdot \Delta \mathbf x $$ That distance is key. In your example, if the size of the container does not change, no energy is expended no matter how long the force lasts. If the force is used ...


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A vacuum will offer you no advantage in cooling your aluminum block, ceteris paribus. In a vacuum, the only method of heat transfer is radiation. You will lose the benefit of any of the other three methods listed below. There are four ways for an object to lose heat: (1) Conduction - Thermodynamic energy is transferred through physical contact with ...


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I can’t write this computer simulation for you (at least not based on the data provided) but will instead explain a few basic relationships that govern the heating and cooling of objects. I hope this helps. Consider a building an object that is composed of $n$ objects of masses $m_i$ with specific heat capacities $c_{p,i}$, then the building has an overall ...


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Thermal diffusivity is the ratio of heat conduction ability to heat storage ability of a material at constant pressure. A high ratio indicates that the material will conduct heat away more readily than it can retain the heat. A low ratio indicates that the material has a great capacity to store heat, and will not be able to conduct heat away as rapidly. ...


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Dr. Robitaille says that blackbody radiation is not universal, even inside cavities where the surfaces are all at thermal equilibrium. That is highly controversial since the electromagnetic fields in a cavity are usually considered as an additional substance, called a "photon gas" which is also at thermal equilibrium and hence has a temperature. This ...


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Certainly, you agree $dH=C_P dT$ if we're at constant pressure. If $H$ and $C_P$ don't actually depend on pressure, then you can use this equation regardless of whether pressure changes. However, to determine $C_P$ and $H$ you first need an equation of state (such as $PV=NkT$). Without knowing the specific equation of state (aka, if your gas is ideal or ...


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Options: Your dish is not actually as cold as you think it is: verify with a thermometer that the dish is actually colder than ambient temperature. Your hand is a terrible thermometer because it does not reach thermal equilibrium with the object you are trying to measure, and so it is sensitive to the thermal conductivity of the substance you are touching. ...


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If I'm not mistaken, a similar effect happens near all sufficiently cold bodies: moisture from the air condenses and becomes visible when cooled from room temperature, a process similar to cloud formation. The reason it stops forming after some time, near ice cream or otherwise, is because the object gradually warms up to room temperature. If the foggy layer ...


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I'll assume this problem is continuous as it makes sense on physics, and not discrete as you wrote on your pseudocode. Its worth pointing out, it makes a huge difference if the problem is discrete or continuous, as I have explained in the comments. However, one can also write a pseudocode for the continuous problem as well: HEATING = 1 # degree per minute ...



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