(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A nonconducting wall carries charge with a uniform denisty of 8.g µC/cm^{2}. What is the electric field 7.00cm in front of the wall? Explain whether your result changes as the distance from the wall is varied.

2. Relevant equations

I'm still really new, I just registered, and trying to find the integral sign and stuff is proving to be pretty difficult

[tex]\int[/tex]EdotdA=Qenclosed/A

E=k[tex]\frac{q}{r^{2}}r[/tex]unit vector

So Gauss's Law and the equation for the electric field, I think, are relevant. The relationship [tex]\sigma[/tex]=Q/A I think is important too. Let's throw in Coulomb's Law for good measure.

F=kqq_{0}/(r^{2})r unit vector

3. The attempt at a solution

Okay, so from my understanding of Gouss's Law, you can use it to calculate the electric field around a closed symmetrical surface that surrounds the thing you want to find the electric field of. Rather, Gauss's Law is a way of counting up the electric field lines. I think I understand how to use Gauss's Law to find the electric field at a point around a sphere of charge; you can just make a Gaussian Sphere around it.

Anyway, I guess my major source of confusion is that you can't really encapsulate a wall, like if it was a rod, or if we could interpret it as a long line of charge, then we could put a cylinder around it. I think I gathered from another post that

E=[tex]\sigma[/tex]/(2[tex]\epsilon[/tex]_{0})

I think that this is the key, but I don't know how this came about. How can this be derived from Gauss's Law or the equation for electric field?

I'm generally pretty confused, and I think I'm going to try to firm up my understanding of applying Gauss's law while I hope that someone replies.

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# Gauss's Law: a nonconductive wall

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