Solving Electrostatic Potential of a Spherical Conducting Shell

In summary, the problem involves finding the electrostatic potential outside a spherical conducting shell with a given charge density. The solution method involves using Green's function with Dirichlet Boundary Conditions and expressing the charge density in terms of spherical harmonics. Simplification may be possible by using a Gaussian surface, but it is not clear where the electric field would be constant for this problem. Further analysis is needed to find a simplified solution.
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hepcats pajamas
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Homework Statement


A spherical conducting shell of radius R is held at a potential V0. Outside the shell,
the charge density is ρ(r) = ρ0sinθcosφ for R < r < 2R. Find the electrostatic potential
everywhere outside the shell.

Homework Equations


Green's function in spherical coordinates between radii a < r < b:
G(r,r') = ##\sum\limits_{l,m} {\frac{4π/(2l+1)}{l-(\frac{a}{b})^{2l+1}} Y^*_{lm}(θ',φ')Y_{lm}(θ,φ)(r^l_< - {\frac{a^{2l+1}}{r^{l+1}_<}})({\frac{1}{r^{l+1}_>}}-{\frac{r^l_>}{b^{2l+1}}})}##

The solution for the potential using Green's function with Dirichlet Boundary Conditions (V is the Volume, S is the boundary surface, n is the normal to the surface):
##Φ(\textbf{r'} ∈ V) = {\int\limits_{V} d\textbf{r} ρ(\textbf{r})G(\textbf{r',r})} - ε_0 {\int\limits_{S} R^2 \: dΩ \: V (\textbf{r}){\frac{∂G(\textbf{r',r})}{∂n}}}##

The Attempt at a Solution


I know the potential at the boundary surface:
## Φ_{S}(\textbf{r}) = V_0 ## where r = R

The normal direction on the surface is r, a = R, b = 2R, so:
at r = R, ## {\frac{∂G(\textbf{r',r})}{∂n}} = \sum\limits_{l,m} {\frac{4π/(2l+1)}{l-(\frac{1}{2})^{2l+1}} Y^*_{lm}(θ',φ')Y_{lm}(θ,φ)((2l+1)R^{l-1})({\frac{1}{r'^{l+1}}}-{\frac{r'^l}{R^{2l+1}}})} ##

The charge density can be expressed using spherical harmonics:
## ρ = ρ_0 {\frac{1}{2}} {\sqrt{\frac{8π}{3}}} (Y_{1,-1}(θ,φ) - Y_{1,1}(θ,φ)) ##

So:
##Φ(\textbf{r'}) = {\int\limits_{Ω}}{\int\limits_{R}^{2R}} r^2 dr \: dΩ \: [ ρ_0 {\frac{1}{2}} {\sqrt{\frac{8π}{3}}} (Y_{1,-1}(θ,φ) - Y_{1,1}(θ,φ)) ] ## ...
... ## [ \sum\limits_{l,m} {\frac{4π/(2l+1)}{l-(\frac{1}{2})^{2l+1}} Y^*_{lm}(θ',φ')Y_{lm}(θ,φ)(r^l_< - {\frac{R^{2l+1}}{r^{l+1}_<}})({\frac{1}{r^{l+1}_>}}-{\frac{r^l_>}{(2R)^{2l+1}}})} ] ## ...
...##- ε_0 {\int\limits_{S} R^2 \: dΩ \: V_0 \: \sum\limits_{l,m} {\frac{4π/(2l+1)}{l-(\frac{1}{2})^{2l+1}} Y^*_{lm}(θ',φ')Y_{lm}(θ,φ)((2l+1)R^{l-1})({\frac{1}{r'^{l+1}}}-{\frac{r'^l}{R^{2l+1}}})} }##

Am I barking up the wrong tree? I am looking for some key simplification. Maybe my approach is over-complicating it, and I should use a Gaussian surface. The issue with that is that I don't see where the electric field would be constant, leading to a simplification.
 
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Thanks for the post! Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
 

Related to Solving Electrostatic Potential of a Spherical Conducting Shell

1. What is the formula for calculating the electrostatic potential of a spherical conducting shell?

The formula for calculating the electrostatic potential of a spherical conducting shell is V = kQ/r, where V is the potential, k is the Coulomb's constant, Q is the charge of the shell, and r is the distance from the center of the shell.

2. How is the electrostatic potential of a spherical conducting shell affected by the charge of the shell?

The electrostatic potential of a spherical conducting shell is directly proportional to the charge of the shell. This means that as the charge increases, the potential also increases.

3. What is the significance of the distance from the center of the shell in calculating the electrostatic potential?

The distance from the center of the shell plays a crucial role in calculating the electrostatic potential. The potential decreases as the distance from the center increases, following an inverse relationship. This means that the potential is higher closer to the center and decreases as you move away from it.

4. How does a change in the charge distribution on the surface of the shell affect the electrostatic potential?

A change in the charge distribution on the surface of the shell can result in a change in the electrostatic potential. If the charge distribution becomes more concentrated in one area, the potential in that area will increase, and vice versa.

5. Can the electrostatic potential of a spherical conducting shell ever be negative?

No, the electrostatic potential of a spherical conducting shell will always be positive. This is because the potential is determined by the charge and the distance, both of which are positive values. A negative potential would indicate a negative charge, which is not possible for a conducting shell.

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