Redistribution of charge in a capacitor

ehild

You can make a glass rod positively charged by rubbing it with cats fur. You touch it to a metal plate: That will be positively charged, too, as some electrons of the metal go over to the glass.

ehild

Ratch

ehild,

Correct, by the absence of electrons, not by any positive charges.

Ratch

ehild

Absence of electrons leaves positively charged particles behind. Yes, because of the excess protons.
Positively charged particles are made in ion guns. Positively charged alpha particles can arise in radioactive decay. There is a material testing method using positrons, also positively charged particles.
There are both positively and negatively charged particles in the world, and they can be isolated.

ehild

Ratch

ehild,

Yes, but the protons are locked into the ionic core of the molecule and cannot move like the electrons can. They certainly do not move in capacitors.

Yes.

A positron is a antimater particle. How are they made and controlled?

Yes, ions in electrochemistry and holes in p-type semiconductor. But not in capacitors.

Ratch

ehild

See http://en.wikipedia.org/wiki/Positron_emission .

Well, what do you think, can an isolated capacitor have net positive charge? You have two metal plates and remove electrons from both of them. Is it possible?

I think you mix "charge" with charged particle. Charge is a property. Anything can have some charge, positive or negative.

The charged particles - electron, proton, positron, ions, - all carry some charge, integer multiple of the elementary charge. In different materials, different particles are the main charge carriers. In metals or semiconductors the main charge carriers are free electrons. In fluids and gases, the charge carriers are mainly ions. But there is ionic conductions also in solids, and ionic conduction is the main conduction process in insulators like glass or in ionic crystals.

ehild

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ehild,

According to the link you gave, it would have to be a radioactive capacitor. But even if you could do it by some electrostatic induction method of taking away electrons, the sea of electrons present in metallic conductors would rush in and neutralize your efforts. That is why holes only exist in semiconductors. It is certainly not practical for a working circuit.

Ratch

MalachiK

So? Why not paint one of the plates with potassium-40? Everyone should have a hobby.