Moving electrical charges and Maxwell's equations

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Discussion Overview

The discussion centers around the behavior of electrical charges, particularly electrons, in relation to Maxwell's equations. Participants explore whether a charge moving at constant velocity can be considered as an electromagnetic wave, the conditions under which radiation occurs, and the implications of acceleration on electromagnetic phenomena. The scope includes theoretical considerations and conceptual clarifications regarding electromagnetic radiation and wave behavior.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that an electron traveling with constant velocity does not radiate as an electromagnetic wave, as radiation requires acceleration.
  • Others argue that while constant velocity does not produce electromagnetic waves, accelerating charges create changing electric and magnetic fields that lead to radiation.
  • A later reply questions whether acceleration must always be oscillatory, suggesting that straight-line acceleration might still produce radiation.
  • Some participants discuss that oscillating charges create steady waves with fixed frequencies, while straight-line acceleration results in transient pulses with a broad spectrum.
  • There is a claim that constant acceleration produces a constant radiation field, although this is contested regarding its implications over large distances.
  • One participant notes that electrons exhibit wave behavior, such as diffraction, even when traveling at constant velocity, raising questions about the nature of these waves.

Areas of Agreement / Disagreement

Participants generally agree that radiation requires acceleration, but there is disagreement about the nature of radiation produced by different types of acceleration and whether constant velocity charges exhibit wave behavior. The discussion remains unresolved regarding the implications of these points.

Contextual Notes

Limitations include the dependence on definitions of radiation and waves, as well as the unresolved nature of how constant velocity charges relate to wave behavior in quantum mechanics.

  • #91
Can we please get a moderator?
 
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  • #92
kcdodd said:
Can we please get a moderator?

Huh? What for? What Wikipedia articles and what equation do you believe is wrong? What kind of discussion is this where I provide all the reference and get called "stupid", yet those who can not support their claims just scream around and wave hands without actually saying anything? Just say it already, what exactly are you so nervous about?
 
  • #93
kcdodd said:
Can we please get a moderator?

I've reported his crazy posts. I recommend others do the same. He can't even tell the difference between charge and charge density, yet he wants to claim every EM book ever written is wrong. This is yet another clear example of how a little bit of knowledge can be a dangerous thing.
 
  • #94
elect_eng said:
I've reported his crazy posts.

He can't even tell the difference between charge and charge density..

Interesting reaction, and I only wanted to see some evidence for your assertions.YOUR FALSE EQUATION: E = \frac{q}{2\pi\epsilon_0*r}

It is you who has a single charge of a single electron in your equation, and moderators will tell you that, whatever the reason you want to call them. You may as well call your mum too, that will not change the reality and what has come to past. Next time be careful about the equations and try to use them before you make your conclusion, so to not embarrass yourself like this. Ok? -- At least you realized there is a TOTAL amount of charges here, now learn about it:

http://en.wikipedia.org/wiki/Coulomb

http://en.wikipedia.org/wiki/Charge_density

http://en.wikipedia.org/wiki/Elementary_charge
 
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  • #95
Dunnis said:
It is you who has a single charge of a single electron in your equation, and moderators will tell you that, whatever the reason you want to call them. You may as well call your mum too, that will not change the reality and what has come to past. Next time be careful about the equations and try to use them before you make your conclusion, so to not embarrass yourself like this. Ok? -- At least you realized there is a TOTAL amount of charges here, now learn about it:

No, it is you that has ignored all of the explanations given to you. I provided you a derivation in an attached jpg file. Did you even look at it after you asked for references and explanations? No you did not. I quoted a book. Did you bother to consult it? No you did not. The variable q is linear charge density with units of Coulombs per meter. It is not the single electron charge as you say. Anybody can go back into this thread and read proof that I explained this. Besides, it needs no explanation. This is such an obvious fact from the context of the equations. You are asking for explanations that are like asking what 2+2 is. Who do you think you are kidding? You are the one who is embarrassing himself.
 
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  • #96
Dunnis said:
YOUR FALSE EQUATION: E = \frac{q}{2\pi\epsilon_0*r}

Why do you call this "my false equation"? This equation can be found in every electromagnetics book. EVERY SINGLE ONE! I gave reference to one book above. The well known book by Krauss is another, and Jackson can be consulted too. I gave a jpg file with my own derivation and kcdoddd gave a link to another derivation. You keep asking for references and we give them, yet you ignore them. What is your problem? Are you just doing this as a prank? Are you just unwilling to admit when you are wrong? Whatever the issue is you'd better come to terms with it. By the way, at one point you mentioned you do this for a living. I dare you to show this thread to your boss, or your customers if you are self-employed.
 

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