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

Click For Summary
SUMMARY

A charge located inside a conducting sphere induces a uniform charge distribution on the surface, resulting in a uniform electric field outside the sphere. The electric field within solid conductors is zero due to the redistribution of charges, which cancels any internal fields. The discussion highlights the misconception regarding the movement of protons and electrons in response to positive and negative charges. The user expresses a desire for a more rigorous proof, suggesting that quantum mechanics may provide deeper insights into these phenomena.

PREREQUISITES
  • Understanding of electrostatics and Gauss's Law
  • Familiarity with electric fields and charge distributions
  • Basic knowledge of conductors and insulators
  • Concepts of surface charge density and electric field calculations
NEXT STEPS
  • Study Gauss's Law in detail to understand electric field behavior in conductors
  • Explore the concept of electric field lines and their implications for charge distribution
  • Investigate the quantum mechanics of charge carriers in conductors
  • Learn about numerical methods for calculating electric fields due to surface charges
USEFUL FOR

Students of physics, electrical engineers, and anyone interested in electrostatics and charge distribution in conductors.

DivergentSpectrum
Messages
149
Reaction score
15
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?
 
Physics news on Phys.org
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?
 

Attachments

  • chargedsphere.jpg
    chargedsphere.jpg
    44.7 KB · Views: 511
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
    torusout.jpg
    43 KB · Views: 449
  • torusin.jpg
    torusin.jpg
    29.9 KB · Views: 514

Similar threads

  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 5 ·
Replies
5
Views
1K
  • · Replies 6 ·
Replies
6
Views
289
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 16 ·
Replies
16
Views
2K
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 14 ·
Replies
14
Views
2K