Beginner Capacitor Question

[Wotan]

I have read about how capacitors work- they store negative charge in one plate and positive in the other. But I don't understand how the charge goes into the plates. I thought charge only flows round a circuit. If a capacitor has an insulator in it, it isn't a complete circuit and so how does the charge flow into the 2 conductive plates?

 

[(*steve*)]

Think of a tank with a rubber diaphragm across it and pipes on either end.

Water can't flow from one pipe to another, but if you pump water in one side, it will deform the rubber so that water flows out the other.

(remembering that if you treat wires like water pipes, they are always full of water, it's just the pressure (voltage) and flow rate (current) that changes.

 

[davelectronic]

Capacitors

Many types of capacitors, but in general you have a posative and negative lead, the charge is stored between posative and negative plates insulated from each other, the charge is stored until part of the circuit puts a load on the capacitor part of the circuit, then its discharged for use, and the process is repeated very fast charge discharge, but depending on the circuit. The net wiki and other tutorials can help as well, try a site called the electronics club if you google that there is a lot there.
Dave

 

[Wotan]

Think of a tank with a rubber diaphragm across it and pipes on either end.

Water can't flow from one pipe to another, but if you pump water in one side, it will deform the rubber so that water flows out the other.

(remembering that if you treat wires like water pipes, they are always full of water, it's just the pressure (voltage) and flow rate (current) that changes.

I don't know what you mean about the rubber diaphragm and how it deforms to be honest.

Many types of capacitors, but in general you have a posative and negative lead, the charge is stored between posative and negative plates insulated from each other, the charge is stored until part of the circuit puts a load on the capacitor part of the circuit, then its discharged for use, and the process is repeated very fast charge discharge, but depending on the circuit. The net wiki and other tutorials can help as well, try a site called the electronics club if you google that there is a lot there.
Dave

Thanks for your reply but I already know that the two plates in a capacitor store charge but I don't know why the positive plate loses electrons and the negative gains electrons in the first place ( when it's charging). I will have to look into it some more maybe I will try electronics club, thanks again.

 

[davelectronic]

Capacitors

Hi again Wotan.
My maths is not brilliant said the guy that likes electronics, me i mean.
Hope you got your physics head on, only joking, have a look at this, also a link to the electronics site club, its all free stuff, and i still pop in there now and again.
Dave.

http://www.kpsec.freeuk.com/

http://www.splung.com/content/sid/3/page/capacitors

Both sites are safe.