Continuous Charge Distribution: Symmetry & Meaning

AI Thread Summary
In the context of continuous charge distribution, "continuous" refers to the charge being spread uniformly over a region or volume rather than being localized at discrete points. This concept contrasts with discrete charge distributions, where charges are concentrated at specific locations. The discussion highlights that even in a continuous current, such as 10^9 electrons per second, the underlying particles are still discrete, leading to phenomena like shot noise due to fluctuations in electron count. The term "symmetry" is also suggested as relevant to understanding these distributions. Overall, continuous charge distributions provide a framework for analyzing electric fields in a more uniform manner compared to discrete distributions.
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In the Electric field of a Continuous Charge Distribution, what is "conti.." exactly?

-I know its the "distribution"! but I`m asking about, like, how would the "distribution" be continuous?
-I think the word "symmetry" should be used?
-why is the word "continuous" used?
 
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In a continuous charge distribution, the charge "fills up" a region or volume of space.

Contrast that with a discrete charge distribution, where the charge might be localized at one single point, or on a collection of point particles.
 


If you have say a current of 10^9 electrons per second (160 picoamps) flowing in a circuit, this is usually consideded to be a continuous current although the signal is comprised of discrete particles. However, if you have a bandwidth of 1 GHz (1 nanosec), there are only about 160 discrete electrons contributing to your signal. There is a Gaussian distribution of electrons in each sample period, leading to a signal fluctuation +/- sqrt(160), called shot or Schottky noise.
 
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