Effect of media on electric force

AI Thread Summary
The discussion explores the impact of surrounding media on the electric force between non-spherically symmetric charges. It posits that the presence of a second medium does not alter the force if the Gaussian surface only encompasses electric field lines in the first medium. The relationship between the charges depends on the local environment defined by the medium they occupy. The conversation emphasizes the importance of applying Gauss' Law or Poisson's equation to analyze such scenarios. Overall, the electric field model is highlighted as a more effective approach for understanding forces in complex media arrangements.
Gavroy
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I was thinking about the following: Assuming that you have NON SPHERICALLY SYMMETRIC charges and they are both in medium 1. Does it make a difference(whereby I am referring to the total force between these two charges) if there is a second medium 2 in the local area of both? So both charges are in medium 1 and there is a medium 2 where some electrical field lines go trough? Does this have any effect on the force if there is another medium where field lines go through?
 
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Set up a specific situation and apply Gauss' Law or Poisson's equation and see.
Is there a special reason the charges need to be non-spherically-symmetric?
 
So no, it does not change anything right?
 
You should do the math :)

Put two charges separated by distance r in medium with relative permittivity ##\epsilon_r## while there is an empty region nearby.
 
but if I take the surface(in Gauss law) such that there are only electric field lines, that are in medium 1, then it does not matter that there is another medium, right? So the electric field is the same. I would thank you if you could confirm this idea, somehow.
 
That's the idea - the force on charge 2 due to charge 1 depends on the charge enclosed by the Gaussian surface and the medium charge 2 is in. At this level, everything is decided locally. That's the advantage of the electric field model - pretty soon you will use electric force less and less and do more and more physics using fields.

(Also look at what happens when the charges are in different media.)

Your reasoning is not bad - you should be able to figure stuff out more confidently with a bit of practice - hint: most of physics is just asking useful questions.

Don't forget the "thanks" button :)
 
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