Linked Questions
10 questions linked to/from What does the concept of "Entropy Flow" mean in detail?
12
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What are entropy and reversible processes really?
I'm confused about the concepts of entropy and reversible processes.
Before explaining the definition of entropy, they used the term "reversible process" without defining it formally. Then, when ...
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3
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What ds>dQ/T mean?
I read the derivation on page 216 over here.
First, it considers an irreversible process between states 1 and 2, followed by a reversible process between states 2 and 1.
From my interpretation, ...
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4
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2
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How to determine the entropy change in a system with heat and mass transfer?
Consider the system as shown in the picture. It consists of two chambers filled with a gas and connected with a tube. One chamber is closed with a piston. Everything is thermally insulated.
We make ...
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2
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2
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Why can one use this equation for entropy if this process is irreversible?
The equation
$$dS = \dfrac{dQ}{T}$$
is said do hold only on reversible processes. Indeed this is almost always emphasized by writing
$$dS = \dfrac{dQ_{\mathrm{rev}}}{T},$$
to be clear that this ...
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4
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4
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Entropy production in isolated system
My question relates to the stereotypical example for understanding the first and second laws: an isolated system filled with a gas of non-interacting molecules with constant ($E$,$V$,$N$) has two ...
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2
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2
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Are the thermoelectric effects reversible?
On the one hand, it is commonly said that thermoelectric effects are reversible. For Wikipedia they are thermodynamically reversible because as the factor of merit ZT approaches infinity, the ...
3
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1
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697
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Entropy production rate due to heat transfer
I don't understand how you can derive a formula for the rate of entropy generation due to heat transfer between two sources with temperatures $T_2$ and $T_1$ without varying the temperature themselves....
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1
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Entropy generated for a warm bath heating a cold rock
Put a cold rock of heat capacity $C_r$ and temperature $T_{r1}$ into an insulated fluid bath of finite heat capacity $C_b$ (the bath is not a reservoir) and temperature $T_{b1}$.
Now let the entire ...
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2
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3
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Is it possible to increase the temperature of an ideal gas in an adiabatic sealed container with a frictionless piston for a lid?
As far as I understand it, if I pumped the piston repeatedly, compressing the gas, the temperature would go up for a second, but the minute I released the piston the higher pressure inside the ...
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2
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1
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Does entropy increase with heat flow?
In an exam, I had a scenario where 2 bodies with different temperatures were put together and over time their temperatures mixed and eventually became uniform. My intuition tells me that as a result, ...
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