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].
16,100 questions
-6
votes
1
answer
63
views
Can anyone explain me entropy intutively not with examples which are from web you own but intuitive? [closed]
im just a 8th grader so come on
- 11
-1
votes
0
answers
22
views
How to construct a generalized system using volume as an extensive quantity in statistical mechanics?
That is, in the generalized partition function.
$$E=\sum\exp{(-\beta E+\xi X)}$$
replacing $X\to V$. However, it is important to note that volume, as an extensive quantity, also acts as a constraint ...
- 115
0
votes
1
answer
95
views
Callen's Thermodynamics - what theory of infinitesimals is Callen using and how can a process with infinitesimal increments be quasi-static?
I am reading the second edition of Callen's Thermodynamics and an introduction to Thermostatics and I have a question that is tangentially related to this (1) and this (2) thread. In both threads, an ...
- 937
-8
votes
0
answers
52
views
harvesting room temp infrared light for free energy [closed]
I'm one of those people who think they can make Free Energy. I got Grok AI to agree with me(https://grok.com/share/c2hhcmQtNA%3D%3D_fc31620a-1089-4906-a216-b4b385f9b03d) and here's a link to ...
6
votes
3
answers
491
views
Why does temperature characterize thermal equilibrium
Thermal equilibrium between thermodynamic systems is defined as a relation that is satisfied if there's no net heat exchange when the systems are put in contact. The zeroth law states thermal ...
- 2,437
0
votes
1
answer
73
views
How do I calculate the maximum possible atmospheric density/ surface pressure a planet can have?
I'm not entirely sure if this is the right stack but here goes.
I'm trying to design a fictional planet that has less gravity than Earth but I would like to give it an atmosphere as or even more dense ...
8
votes
5
answers
1k
views
How could an infinitesimal transfer of heat even be possible if we already have equilibrium?
I am reading the second edition of Callen's Thermodynamics and am a little confused about an example he presents. The example is outlined below and can be found on page 101.
In the simplest case we ...
- 937
0
votes
1
answer
65
views
Why is such heat transfer necessarily quasi-static?
I am reading p. 101 in the second edition of Callen's Thermodynamics and an Introduction to Thermostatics, and I am a little confused. I understand that a quasi-static process is a transformation ...
- 937
0
votes
1
answer
90
views
When can an asteroid have an atmosphere?
I was reading about the atmosphere of the Moon, which by all practical definitions is non-existent. The whole atmosphere has a mass of less than $10$ metric tonnes, which is the approximate mass of $...
- 307
0
votes
0
answers
70
views
Are these definitions of electrochemical potential the same? [closed]
I have been reading the second edition of Callen's Thermodynamics and an Introduction to Thermostatics independantly from my thermodynamics course at university and Callen defines the electrochemical ...
- 937
0
votes
0
answers
50
views
Can mixing be a thermodynamically reversible process? [closed]
I understand that adiabatic mixing is necessarily an irreversible process since there is an internal entropy generation in the system, and the entropy of the surroundings remains the same, so the net ...
- 21
0
votes
0
answers
59
views
What size pipe and flow rate? Wood fired water heater [closed]
THE QUESTION:
For my 6600-gallon above-ground pool that has a salt water chlorine generator on it, I am going to set up a wood barrel or fire cage that will host a coil of 316 stainless steel. I'm ...
- 1
13
votes
5
answers
2k
views
Why 1st law of thermodynamics is applied to cosmological expansion?
In the standard FLRW cosmology, the "conservation" of energy follows from the equation of stress-energy tensor of matter:
$$
\nabla_\mu T^\mu_0 = 0.
$$
Expanding it we get
$$
-\frac{\textrm{...
- 1,686
0
votes
1
answer
55
views
What is the effect of potential energy on kinetic energy of real gas?
My question is that in real gas can potential energy decrease or increase kinetic energy and change the temperature by changing kinetic energy.
- 31
0
votes
1
answer
145
views
Why does Callen's general reasoning not encompass a solid body?
I have been reading the second edition of Callen's Thermodynamics and an Introduction to Thermostatics recently and have a question tangentially related to the meaning of a "wall". Callen, ...
- 937