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PhDorBust
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We have a uniformly charged sphere (charge is all over, not just on surface) and want to determine the electric field at a point that is distance X from the center of the sphere. The radius of the sphere is known.
I first derived the electric field from a disk to a point that is distance x away from the center of the disk.
s = surface density = Q/A
ep = permitivity of free space constant
r = radius of sphere
R = radius of disk
I found this to be [s/(2ep)]*[1 - x/sqrt(x^2 + R^2)]
Now I have to integrate this from X - R to X + R. But I cannot figure out how to express the radius of the disks in terms of the sphere radius without introducing more variables (ie angle variable).
I am also confused as to how exactly to correlate surface density with volume density.
I wish to use Coulomb's Law and not Gauss'.
I first derived the electric field from a disk to a point that is distance x away from the center of the disk.
s = surface density = Q/A
ep = permitivity of free space constant
r = radius of sphere
R = radius of disk
I found this to be [s/(2ep)]*[1 - x/sqrt(x^2 + R^2)]
Now I have to integrate this from X - R to X + R. But I cannot figure out how to express the radius of the disks in terms of the sphere radius without introducing more variables (ie angle variable).
I am also confused as to how exactly to correlate surface density with volume density.
I wish to use Coulomb's Law and not Gauss'.