Electric field and gauss law for different models of sphere

AI Thread Summary
The discussion centers on applying Gauss's law to different models of spheres, specifically regarding electric fields and charge distributions. It is clarified that a charge placed at the center of a spherical shell does not affect the shell's surface, resulting in an electric field of zero inside a solid sphere with charge uniformly distributed on its surface. The confusion arises between a charge uniformly distributed on the surface and a symmetrical spherical charge distribution, which requires charges to be evenly spread throughout the volume. Achieving a spherical symmetrical distribution can theoretically occur in scenarios like neutron stars, where charge equilibrium leads to a uniform distribution. Overall, the conversation emphasizes the distinctions in charge distribution and the implications for electric fields in spherical geometries.
exuberant.me
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Hello all! I actually have a few doubts regarding "gauss law" when applied "for different models of sphere"

First, If we place a charge 'Q' inside a spherical shell at the center (somehow) then it should come out to its surface that means in no way can we do it. True or False?

Next,

Considering a solid sphere having a charge Q uniformly distributed on its outer surface. Thus everywhere inside it is the electric field equal to 0.

But i have somewhere read that the electric field inside a solid sphere is Kqr/R^3.

Or is it that , there is a difference in these two statements
"A charge uniformly distributed on the surface of a solid sphere" and
"A symmetrical spherical distribution of charge" ?

Also, How can we get a spherical symmetrical distribution of charge?
. By placing the charge at the center of the solid sphere? (which is again impossible i guess)

I'll be greatly thankful if someone clears these brain storming doubts?
 
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hello exuberant.me! :smile:

(try using the X2 button just above the Reply box :wink:)
exuberant.me said:
First, If we place a charge 'Q' inside a spherical shell at the center (somehow) then it should come out to its surface that means in no way can we do it. True or False?

sorry, no idea what you mean :redface:
But i have somewhere read that the electric field inside a solid sphere is Kqr/R^3.

Or is it that , there is a difference in these two statements
"A charge uniformly distributed on the surface of a solid sphere" and
"A symmetrical spherical distribution of charge" ?

yes … Kqr/R3 is for a charge uniformly distributed throughout the volume (use gauss law! :wink:)
Also, How can we get a spherical symmetrical distribution of charge?
. By placing the charge at the center of the solid sphere? (which is again impossible i guess

no, by chucking the charges in, and giving them a good old stir

like making a pudding :smile:
 
tiny-tim said:
like making a pudding :smile:

With no lumps, of course... nice and smooth...
 
exuberant.me said:
Also, How can we get a spherical symmetrical distribution of charge?
mathematically,
\frac{\partial \rho}{\partial \theta} = \frac{\partial \rho}{\partial \phi} = 0
and practically how this could happen for a solid sphere with fixed charges? ...err... maybe in Neutron stars that have a surplus of electrons? The electrons wouldn't be fixed, but in equilibrium the charge distribution would be spherically symmetric... unless it was a pulsar?

So you just have to make a neutron star :) easy-peasy.
 
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