Electric Field: Why is This Statement Wrong?

AI Thread Summary
The discussion centers on the misconception that the electric field on a Gaussian surface is influenced by charges outside that surface. It emphasizes that Gauss's law pertains to electric flux and is primarily determined by the enclosed charge. Participants explore the implications of enclosing an electric dipole and how the electric field behaves as the distance between charges changes. The consensus is that while the distribution of the electric field can vary, the total electric flux remains constant. Understanding these principles clarifies why external charges do not affect the electric field within the Gaussian surface.
yti1211
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y is this statement wrong?

The electric field on a gaussian surface is generally not influenced by charge that is not enclosed by the surface.

ps: isn't the electric field proportional only to the ENCLOSED CHARGE, but not the outside charge?? :confused:

This is getting me so fRustrated
 
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Gauss law is a law of electric flux, not E-field. If the situation is symmetric enough, you may extract the value of the E-field from it. Consider a Gaussian surface enclosing an electric dipole. Are you able to determine the E-field at any point on the surface? Now imagine the distance between the positive and negative charges increasing along with the size of the Gaussian surface. What is the E-field at any point on the surface?
 
hmm, first, thanks Defender! I no that u need a constant E throughout the Gaussian surface in order to extract E from the integral. but how do you explain why the E- field on Gaussian surface is affected by a charge outside of the surface?? because the ENCLOSED Q is the key right? or do u mean the size of the Gaussian surface is changing when a charge is placed outside of it?

THXXX :)
 
ohh, I think I got it now! So the distribution of E field is changing on the Gaussian surface, but the total E dA is the same. yAy
 
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