# Charge on acpacitor

1. Jul 5, 2007

### pardesi

why is there equal charge on both the capacitor when one end of one and the other end the other is connected to a battery

2. Jul 5, 2007

3. Jul 5, 2007

### ice109

hes asking why equal but opposite charges develop on opposite sides of a parellel plate capacitor and the answer is because they have to setup an E field that cancels out the field of the battery

4. Jul 5, 2007

### pardesi

well here i am not using any speciality of the 'capacitor'...i just use 4 plates connect two of them to a battery and place two of the other after connecting them by a perfectly conducting wire in between the two plates....will the charge distribution be $$Q,-Q,Q,-Q$$ respectively ...if yes why

i am trying to proceed on the lines of uniqueness theorem for electric fields...

5. Jul 5, 2007

### ice109

i told you why, because charge travels down a potential gradient and since a cap is an open circuit it will stop at the plate and create a field.

6. Jul 5, 2007

### ranger

This is a very interesting question. You will find this discussion of interest:
http://www.usna.edu/Users/physics/mungan/Scholarship/Capacitors.html

7. Jul 6, 2007

### pardesi

hey thanks for that wonderfuls site.
i got a proof on the line that the there is no charge deposition on the wire and assuming steady state