Talk:Drift velocity

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Untitled

i think this article is only a stub, so i put the tag on the test.

As it relates to guiding center drift theory

I think more discussion as it relates to Guiding center drift theory, since essentially the whole theory is essentially about finding "drift velocities". For now, I'll add Guiding center to "see also" IlyaV (talk) 02:39, 18 February 2010 (UTC)

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Many information is absent.

Equation Error:

∂Q = (nAv)q is surely not correct. The right-hand side is equal to the current, not the change in Q. Either the LHS should read "I" or the RHS should include "dt" in the numerator. -- Anonymous

More changes are desirable

I just made some cosmetic changes now, but more changes are necessary. Probably rho for charge density is confusing in a context where rho is commonly used for specific resistivity. The article is also incomplete. I would have expected a relation with the relaxation time tau here. /Pieter Kuiper 11:44, 20 September 2007 (UTC)

Electron velocity

I just redirected this term to here, as they are essentially the same aren't they? The text of the article is below.

{{Unreferenced|date=February 2007}}

Electron velocity is a very important value in computing. Electron is the subatomic particle responsible for electromagnetic field, that's the way to transmit information in electronic hardware. In a metallic atom the electrons on his orbit are relatively free to move from an atom to one other; this movement is cause of current, which is an electron's flow.

According to relativistic model electron in an hydrogen atom would be moving at 2.42 x 10⁸ cm/sec.

For now, the most widely-used material with high electronic velocity is silicon, but faster ones are possible:

1. Gallium arsenide
2. Indium(III) phosphide
3. Indium gallium arsenide

{{electronics-stub}}

{{comp-sci-stub}}

Assessment comment

The comment(s) below were originally left at Talk:Drift velocity/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

in the absence of eletricfield an eletrone have only thermel velocity.when a uniform eletric field is applied to the conductor,then the eletron get accelerated in the direction of the field and the eletroe move in the direction opposite to the field. this velocity of eletron due to the presence field is called DRIFT VELOCITY

Last edited at 04:39, 1 August 2008 (UTC). Substituted at 13:51, 29 April 2016 (UTC)

Dimensional Analysis

please check dimensions.

THE ASG.

106.192.176.37 (talk) 21:49, 20 September 2016 (UTC)

Variables

I noticed that this article uses a lowercase "u" for drift velocity. However, many textbooks use v or v_d for drift velocity. In fact, v_d is used in the Wikipedia article on current density. I would like to propose that we switch to v_d throughout this article. What do other people think? Is there a good reason for using "u"? Navigatr85 18:08, 18 May 2018 (UTC) — Preceding unsigned comment added by Navigatr85 (talk • contribs)

The article is a bit misleading

It is currently claimed that "In general, an electron will propagate randomly in a conductor at the Fermi velocity. An applied electric field will give this random motion a small net flow velocity in one direction.". This is wrong. In the free or nearly free electron model, the free electrons (i.e. not the core electrons tightly bound to the nuclei) obey Fermi-Dirac statistics as well as Pauli's exlusion principle. This means their velocities range from 0 up to roughtly the Fermi velocity. So, we cannot really speak of an electron velocity in general, although we could speak of an average velocity but this would serve no purpose whatsoever. Instead, only the electrons that have a momentum near the Fermi momentum can take part in electrical conduction. In this sense, it is only these very few free electrons that have such a velocity that indeed propagate at the Fermi velocity. This is far from an electron in general, even free ones.

Thus a possible way to fix the current Wikipedia sentence could be something like "Following the free electron model, in a conductor the few free electrons that can take part in electrical conduction propagate randomly in at speeds near the Fermi velocity. An applied electric field will perturb the electrons that are going in the field's direction at the Fermi velocity, to change their momentum in the opposite direction with approximately the same speed. The net result is a small drift velocity in the opposite direction than the electric field." — Preceding unsigned comment added by 176.163.163.86 (talk) 11:37, 3 January 2019 (UTC)

Physics

Why Current and the direction of flow of electrons are Opposite? 2409:4043:61D:8F96:5115:2CDD:6B7D:63B6 (talk) 02:12, 29 January 2022 (UTC)