Why is the Electric Field Constant Along a Charged Cylinder's Surface?

AI Thread Summary
The electric field along the surface of a uniformly charged cylinder is constant due to the symmetry of the charge distribution. Gauss's law is applicable, primarily for infinitely long rods, but it provides a good approximation for finite lengths if the observation point is far from the ends. The electric flux through the caps of the Gaussian surface is zero because the electric field lines are parallel to these surfaces, resulting in no contribution to the flux. This uniformity in electric field intensity is a key characteristic of cylindrical symmetry. Understanding these principles is essential for accurately applying Gauss's law in electrostatics.
Godwin Kessy
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Am really suprised when deriving electric field due to a uniform charged thin long rod! It was suprising to have a cylinder as a gausian surface!

actualy is that posible, that all along the surface of the cylinder has same field intensity and why?

also why are there no electric flux along the caps of the gausian surface "the cylinder"
 
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Godwin Kessy said:
Am really suprised when deriving electric field due to a uniform charged thin long rod! It was suprising to have a cylinder as a gausian surface!

actualy is that posible, that all along the surface of the cylinder has same field intensity and why?

also why are there no electric flux along the caps of the gausian surface "the cylinder"

Technically, Guass' law only works for an infinitely long rod. If the rod is shorter than infinity, Guass' law is just an approximation. But it makes a pretty good approximation if you are not dealing with anything close to the edge of the rod, and you are much closer to the rod than the rod is long.
 
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