Physics Electrostatics Question

[Sneha_rk]

Homework Statement

Why do charged particles come to the surface of a conductor if there is no repulsions between them (the charged particles), as suggested by Columb's Law?

Homework Equations

Columb's Law
F=kq₁q₂
r²

The Attempt at a Solution

The permittivity of a conductor is infinity. So according to columb's law, the force of attraction between any two particles in a conductor is zero, because any number divided by infinity is zero. But charged particles are found only on the surface of the conductor. How did they get there? How do they stay there?

Would chemical bonding have anything to do with the answer?

 

[gneill]

It's not a trivial question to answer. The permittivity constants that we're used to dealing with are a simplified form. For complex materials with varying degrees of conductivity and dependencies on frequency of field oscillations the permittivity is a complex value (real and imaginary parts). It is often easier to simply assume the known behavior of charges and fields for conductors and insulators than to delve into the details of what is going on with the characteristics of space inside them!

https://www.physicsforums.com/showthread.php?t=328298" to a similar thread that took place a while back. It may give you some insight (or perhaps added confusion!).

 

[supratim1]

hello Sneha...Welcome to Physics Forums!

in a conductor, the charges come to the surface, so that electric field inside it is zero. if it was non-zero, then there would be a current inside the conductor, which would violate conservation of energy.

 

[Sneha_rk]

That makes sense. Thanks!
I also that heard it is explained in Gauss Law, but we haven't completed that in class.

 

[supratim1]

welcome. yes Gauss Law is used to explain it. study it and you will understand. you are in class 11 i suppose.

 

[Sneha_rk]

I think I'll just wait for it to be explained in class.
Actually, no. 9th. :-/
Aah, corporate schools. They make so much sense, don't they?