Gaussian Surfaces and infinite lines of charge

AI Thread Summary
The discussion centers on the differences in electric fields generated by an infinite plane of charge versus an infinite line of charge. For an infinite plane, the electric field remains constant regardless of distance, while for an infinite line of charge, the electric field varies inversely with the radius of the cylindrical Gaussian surface, as described by the equation E = (charge density)/(2∏ε * r). This discrepancy raises questions about the consistency of these concepts in electrostatics. The user seeks clarification on how these two scenarios align or differ in terms of electric field behavior. Understanding these principles is crucial for grasping the fundamentals of electrostatics.
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So I've been wondering..
from my previous post: https://www.physicsforums.com/showthread.php?p=4500082#post4500082

if we have a plane of infinite charge, then electric field does not depend on distance

however, for a infinite line of charge:
If we use a cylinder with radius 'r' as our gaussian surface then
the electric field has the equation

E = (charge density)/ (2∏ε * r)

which now depends on the radius of the cylinder.

This suggests that the electric field actually will have different values for different radius values
which (i feel) don't line up with the conclusion I reached in my first thread 'if we have a plane of infinite charge, then electric field does not depend on distance'

Any help?
 
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