# Tagged Questions

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### Reversibility and isothermal processes

I would like to know why any reversible process has to be isothermal, according to my sources. Why can´t we consider adiabatic processes to be reversible? EDITED https://www.ohio.edu/mechanical/...
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### Inequality of Clausius

I'm having some trouble understanding the inequality of Clausius. My treatment of the inequality applies to an engine operating in a cycle between two temperatures (i.e. like a Carnot engine). The ...
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### Entropy and Clausius inequality

From the Clausius inequality we can derive that the efficiency of a Carnot (reversible) cycle is given by: $$e= 1 - \frac{T_c}{T_h}$$ Is this true for every reversible cycle? Is the efficiency of all ...
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### 2nd law of thermodynamics' violation?

According to 2nd law of thermodynamics, it is not possible to convert heat 100% into work. Well, investigating about the Carnot Cycle, I have found out that in the first step, the process is to heat ...
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### Carnot cycle equation

How to prove the relation $\frac{Q_{given\space out}}{Q_{absorbed}}=\frac{T_{cold}}{T_{hot}}$ by only writing equations using first law?
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### Understanding the Carnot cycle

My textbook explains the Carnot cycle as follows: Heat is added to the boiler, where the steam inside expands isothermally at high temperature (T(High))--(both valves closed). The intake valve is ...
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### How to define the thermodynamic temperature

I've been reading derivations of the thermodynamic temperature scale. I'm assuming these are using Kelvin's method. I follow the math and the conclusion of the argument, but I don't understand how it ...
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### 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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### 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 ...
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 ...