All Questions
Tagged with mean-free-path thermodynamics
9
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How is number of collisions per unit distance related to mean free path?
Recently I have been studying Kinetic Theory Of Gases, with one of the topics as collision frequency. I know that collision frequency is inverse of relaxation time which is also the measure of number ...
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Mean free path of molecules
So in the book concepts in thermal physics(by Stephan and Katherine Blundell) the expression of mean scattering time is derived as shown(please refer the book for more). If we replace vdt in the ...
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Question regarding correction factor in Mean free path
1)The expression for $Mean$ $Free$ $Path$ (ie) ,
$$λ=\dfrac{1}{πd²\dfrac{n}{V}}$$ is derived under the assumption that the particles except the one( let's consider it as particle $A$) you're ...
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What does ultra-rarefied gas mean?
Without using any math, can you explain to me what a rarefied gas is? And then what an ultra-rarefied gas is? I'd like to understand it from a conceptual level if you can make connections to other ...
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What is the mean free path (MFP) of a Cosmic microwave background radiation (CMBR) photon?
If the IGM (inter-galactic medium) had a massive particle (proton) every cubic metre, or a carbon grain every cubic kilometre, what would be the MFP of a CMBR photon? The coherence length of the ...
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How can mean free path affect the propagation of sound in a gas?
I was thinking, since mean free path is a measure of "how long" a particle has to travel to collide with another, that this surely must influence sound propagation somehow. I would say this ...
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3
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In particle physics what is the derivation of the mean free path length: $\ell=\frac{1}{n \sigma}$?
From my lecture notes (ICL, dept. of Physics) it is written:
Consider a thin piece of material with thickness $d$ containing target particles with number density $n$, as illustrated in Figure $\bf{2....
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Why does thermal conductivity decrease from solids to gases?
I am learning in my heat transfer class that the thermal conductivity decreases from solids to liquids to gases i.e.
$$K_{solid} > K_{liquid}>K_{gas}$$
The reason cited is that (based on my ...
user238352
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Mean free path of electron in air?
I'm interested in approximating the mean free path of an electron in air. I think I'm going to need to add something more into my approximation because currently I calculate $400m$ for the mean free ...
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