# Electromagnetism: Force between two charged plates

Homework Statement:
Coulomb's Law: finding electric force between two metal plates.
Relevant Equations:
F=q1*q2/(r^2) (unit position vector)
Hello, I need to find the force between the two metal plates, one is charged positively, and another is charged negatively.
I have to use surface integration, but then I get two surface integrations because of the two differently charged plates.
Thank you in advance

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## Answers and Replies

haruspex
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Homework Statement:: Coulomb's Law: finding electric force between two metal plates.
Relevant Equations:: F=q1*q2/(r^2) (unit position vector)

I have to use surface integration, but then I get two surface integrations because of the two differently charged plates.
Do you mean you get a double integral?
The difficulty, surely, is that the distance between the area elements varies.
Being metal plates, the charge distribution will not be quite uniform, but I would treat it as such.
What is the usual approximation of the field near a large charged plate?