Charge on the surface of a sphere induced by a charge inside

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Discussion Overview

The discussion revolves around the behavior of electric fields and induced charges in conductors, particularly focusing on a charge placed inside a conducting sphere and its effects on the surface charge distribution and electric field. Participants explore theoretical concepts, seek clarifications, and express frustrations regarding the understanding of these phenomena.

Discussion Character

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

Main Points Raised

  • One participant expresses confusion about the uniform electric field created by a charge inside a conducting sphere and questions the reasoning behind the zero electric field within solid conductors.
  • Another participant suggests that the movement of excess electrons in a conductor is driven by their repulsion, leading them to the surface, but questions whether protons would move to the surface if the charge were positive.
  • A different viewpoint indicates that a positive charge would cause electrons to move inward, resulting in a more positive charge on the outside of the conductor.
  • One participant expresses dissatisfaction with existing explanations and suggests that understanding these concepts may require delving into quantum mechanics.
  • A participant introduces a related topic about the function of spheres on charge bleeder lightning rods, prompting further inquiry.
  • Another participant discusses their numerical calculations of the electric field due to surface charge and raises questions about the behavior of the electric field on the surface of a torus with uniform charge density, noting that the electric field inside the torus is not zero.

Areas of Agreement / Disagreement

Participants exhibit a range of views and uncertainties regarding the behavior of electric fields and induced charges in conductors. There is no consensus on the explanations provided, and several questions remain unresolved.

Contextual Notes

Participants highlight limitations in their understanding and express the need for more foundational explanations. There are references to existing literature and prior knowledge that do not fully address their questions.

DivergentSpectrum
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Im having trouble convincing myself that a charge located anywhere inside a conducting sphere will create an induced charge on the surface of the sphere with an electric field that is completely uniform. This doesn't make much sense to me.

Also same with how the electric field inside solid conductors is zero, but to a lesser degree(i get the idea that the induced charge will cancel out the initial field, but I am still kinda unsatisfied)

Do i just have to deal with it and go on until i get into more advanced stuff, or is there some kinda explanation/proof for it?
 
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The excess electrons repel each other, so they want to get as far away from each other as possible. To do this they move to the surface of the conductor.
I guess this makes sense if the charge of a conductor is negative, but if the charge is positive does that mean protons are moving to the surface?
the charge in a hollow sphere explanation didnt make much sense either
 
No, I think the positive charge causes the electrons to move inward leaving a more positive charge on the outside.
 
still doesn't help me much. the page you showed me was pretty much the same explanation that griffiths introduction to electrodynamics gave. Oh well I am moving on as I am guessing the only way this could be proven is by studying the quantum mechanics of the individual atoms.
I hate how physics can't be approached in a "theorem by theorem" or even an axiom by axiom approach
 
Have you ever noticed those spheres on charge bleeder 'lightning rods', what do you imagine they are doing, or do you think they're just decorative?
 
Hmm, i tried looking for some kind of designs for them but couldn't find any.
Also, a (somewhat) unrelated item:
I was playing around with a program i made that numerically calculates the e field due to a surface charge, and i found that on the surface itself the e field is tangent to the surface. I understand that on the surface the e field will be approaching zero. (while out side it will be inverse square proportional in distance to the center of the sphere)
but this got me thinking, what is the e field ON the surface itself?
 

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also, i used the surface of a torus (with uniform charge density)
the first photo shows the outside of the torus which looks right, but inside the E field inside is clearly not zero.
does this mean i did something wrong?
 

Attachments

  • torusout.jpg
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  • torusin.jpg
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