In a certain region of space, the electric field E is uniform.

AI Thread Summary
In a uniform electric field, the charge density is zero because a uniform field indicates a balance of forces with no net charge present. If there were charges, they would distort the electric field, preventing it from being uniform. The discussion also raises the question of whether the electric field must be uniform in a region with no charge, concluding that it does not have to be, as external charges can influence the field. Thus, the presence of external charges can create a non-uniform field even in a charge-free region. Overall, uniform electric fields correlate with zero charge density, but do not guarantee uniformity in the absence of charge.
xxaznitex
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Homework Statement



In a certain region of space, the electric field E/vec is uniform.
Why is the charge density in this region zero?
Assume in a region of space where there is no charge, must E/vec be uniform?

Homework Equations



Gauss's Law

The Attempt at a Solution



I don't really know why a uniform electric field makes the charge density zero... The only thing that I know I could do would be to make this "area" so large (to infinity) that the resulting density would be zero. Can anyone explain to me why?
 
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If there was a charge would the field be uniform?
 
No because the charge would cause a distortion of the field?
 
That would be my thinking.

What about a region with no charge? Must the field be uniform?
 
Hmm, I would say no, because the charge can be right outside the area with no charge..?
 
xxaznitex said:
Hmm, I would say no, because the charge can be right outside the area with no charge..?

Precisely.
 

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