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Electrostatics Problem?
Could anyone help me with this Guassian Surfaces problem?
Consider a spherically symmetric charge cloud with a charge density which falls off as p(r) = A/r for r < R and it is zero everywhere else. For this charge density distribution write down an expression for the charge in a thin shell from r to r +dr, if r < R.
1 Answer
- DavidLv 66 years ago
Surface area of a sphere is 4*pi*r². For a small enough dr, you can say that the inner area is approximately equal to outer area of this shell, so volume of this thin shell is the area times dr, so it would be 4*pi*r²*dr. If the charge density is per volume then you have the charge in this shell equal to p(r)*4*pi*r²*dr. I do not know what A represents in your formula.
