Induced charge density -- non-zero potential case

AI Thread Summary
Induced charge density occurs on the surfaces of closed conductors with non-zero charge, differing from grounded cases commonly discussed in textbooks. To find this charge density mathematically, one must solve Poisson's equation, which can be analytically solved only for regular geometries. For arbitrary shapes, techniques like Finite Element Analysis (FEA) are necessary. The discussion also seeks examples and solutions related to calculating charge density using FEA methods. Understanding these concepts is crucial for addressing complex electrostatic problems in non-grounded scenarios.
mertcan
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Hi, Let's think 2 arbitrary shape conductors with non zero charged. If these 2 conductors are closed, there will be induced charge density over surfaces of these conductors. I have not seen such an example, instead there are lots of problems which involve zero(grounded) potential case and method of images theorem is applied. So, I am asking how can we mathematically find induced charge density over conductors' surfaces including non zero potential case(not grounded)?
Thanks...
 
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Finding charge density distribution involves solving Poisson's equation ## \nabla ^2 U = - \frac {\rho}{\epsilon \epsilon_0} ##.
This equation can be solved analytically only in some simple cases when the geometry is rather regular (e.g. planar, cylindrical, spherical, etc.) and these you find in textbooks. In other cases, you can get a power (or other) series expansion. But if you want to solve the Poisson's equation for a completely arbitrary shapes (conductors, dielectrics) you have to use Finite Element Analysis or similar methods.
 
Then, please let me ask the following question: I am really looking for that kind of examples, could you tell me how I can find some examples and solutions related to calculating charge density with finite element analysis ?
 
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