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Example of a Carnot machine made of a different physical system than a ideal gas?

Anybody knows an example of a Carnot machine made with any different thing than a gas? For example wire or a magnet. I was wondering that since I read the Kardar's book on Statistical Mechanics. He ...
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Plotting isothermals and adiabats

first time poster in this site. I am trying to create a small program to make a graph of the Carnot cycle. For isothermals I am simply trying to look for points where P*V would give the same ...
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A system with temp T is in contact with a reservoir of temp T. Would the system ever take in energy and expand (do work) in this situation?

The context is explain a Carnot cycle and how to get work from a system. Its starts by saying the system is in equilibrium with its surroundings, but then it take in some energy Qin. How does ...
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Is there any difference between heat and entropy here?

This screenshot is from the Carnot Cycle page on Wikipedia. In the "Stages" section, it says that: The gas expansion is propelled by absorption of heat energy, $Q_1$, and of entropy, $\Delta S=Q_1/...
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Irreversible heat engines strictly less efficient than reversible ones

I understand how Carnot's theorem implies that irreversible heat engines must be no more efficient than reversible one's, but it is less clear why they need to be less efficient, as I have seen stated ...
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Carnot cycle in steam processes

Our professor told us that in steam processes, such as Clausis-Rankine process, Carnot's cycle is impossible to achieve. Can someone explain why?
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In a heat pump, why is $Q_{h} - Q_{c} = W_{on}$?

I need help patching up the current holes in my understanding of a heat pump's process. I've explained my understanding and questions that accompany it. The standard explanation as to why $Q_{h} - ...
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130 views

Entropy change in a reversible carnot cycle with 2 beakers

Consider 2 beakers each containing 1kg of water. One beaker has initial temperature of 25 degrees celsius and the other at 100 degrees celsius. The beaker are now mixed. Assuming no heat exchanged is ...
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21 views

Isochoric Kelvin Plank - Clausius Equivalence

As the Clausius statement is underpinned by the assumption that W=P.∆V Therefore ∆V=0 , W=0 Can anyone restate the Kelvin Plank-Clausius Equivalence Proof considering a solely Isochoric process ...
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30 views

Efficiency of a Carnot refrigerator without knowledge of the temperatures

We know that in a Carnot refrigerator we can express the efficiency as $$\eta = \dfrac{Q_1}{Q_2-Q_1}=\dfrac{T_1}{T_2-T_1},$$ where $T_1$ and $T_2$ are temperatures of the reservoirs between which ...
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82 views

Carnot cycle's paradox

Carnot cycle is a reversible cycle. By definition a reversible cycle must have an infinitesimal temperature difference. That means ($T_{high}-T_{low}$) is very very small. Any finite temperature ...