All Questions
Tagged with mean-free-path statistical-mechanics
14
questions
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Mean free path equation for plasma
Does the mean free path equation
$$\lambda=\frac{1}{\sqrt{2}\pi d^2 n_v}$$
work for collisions in plasma or just for gas?
- 33
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Standard deviation for a free path distribution
I would like to be able to describe a particles path before collisions with greater precision. We can calculate the "mean" free path of a particle before colliding moving particles, but I ...
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1
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Why does computing mean free path from an air molecule's reference frame seem to greatly overestimate path length?
I was interested in seeing if I could derive the mean free path of an "air molecule" by considering the reference frame of an individual molecule as other particles moved around it randomly. ...
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2
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1
answer
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How does $\frac{\langle v\rangle}{\langle v_r\rangle}=\frac{1}{\sqrt2}$ imply the formula for the mean free path?
In this question, it was asked how the formula $$l=\frac{1}{\sqrt 2n\sigma }$$ can be rigorously derived for a Maxwell-Boltzmann gas.
Here $l$ is the mean free path length in a gas, $n$ is the gas ...
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Free Path Probability Distribution for an Ideal Gas
Suppose we have a gas with collisions. The mean free path, $l$, is the average distance a particle travels before colliding with another particle. This is the average, but what is the probability ...
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Collisional cross-section from attenuation factor
I am trying to find the mean free path of silver atoms travelling through air (I am given the temperature, pressure and that they are attenuated by a factor $2.72$ in a distance of $10^{-2}$m).
I know ...
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How to calculate the free mean path of electrons in the gas mixture? [closed]
How to calculate the free mean path of electrons in the gas mixture? I understand (a little bit) the mean free path concept for the atomic collisions but I am not sure what to do if I am interested in ...
user148787
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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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Rigorous derivation of the mean free path in a gas
Can anyone supply me with a derivation of the mean free path, of
particles in a Maxwell Boltzmann Gas?
Cited in various literature is the formula,
\begin{align}
\begin{split}
\ell&=\frac{1}{\...
- 579
1
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2
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Most probable free path length
The distribution of scattering time is
$nv\sigma e^{-nv\sigma t}$
where $\sigma$ is the collision-cross section, $n$ is the number density of molecules and $v$ is the average relative velocity. This ...
- 155
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How photons get distributed in a system?
Let's say I'm in a room, and there are plenty of things in my room like carpet,mirrors,glass and other stuff.And I see there are shadow regions and fully bright regions, and I want to know how photons ...
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6
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Does it make sense to define the mean free path in quantum mechanics?
The mean free path defined in classical molecule dynamics has a strong classical flavor. Is it sensible to generalize the idea to quantum mechanics?
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4
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2
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RMS Free Path vs Mean Free Path
I am trying to determine the mathematical difference between mean free path and root-mean-square free path. For an ideal gas, the relaxation time is $$\tau=\frac{1}{\sqrt2 \pi nd^2 \bar v}$$ and the ...
- 1,158
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Energy of particle in electric field
I'm taking a physics class and the professor teaches us really basic things in lecture and then gives homework way beyond what he taught in lecture. Obviously I need to find some resource other than ...
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