Finding the potential of a conducting disk(without laplace)

AI Thread Summary
The discussion revolves around finding the electric potential of a conducting disk in space without using the Laplace equation. The user proposes utilizing the potential of a uniformly charged rod, as its equipotentials form ellipsoids, with the disk being a limiting case of an ellipsoid. They express frustration with the mathematical complexity involved in transitioning from the rod's potential to that of the disk. Alternative methods, such as brute force integration with the free space Green's function, are suggested but deemed unnecessarily complicated. Ultimately, the user believes that leveraging the established potential of the rod and adjusting parameters is a more straightforward approach to derive the disk's potential.
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I want to find the potential of a conducting disk in space whithout laplace equation.(i know how to do that).I want to use the potential of a uniformly charged rod.because its equipotentials are ellipsoids(ellipses rotated around the rod).now a disk is a limiting case of an ellipsoid.
I can't get through the math part.can someone write and simplyfy it?
because a disk is an ellipsoid where semi major axis approaches zero and semi minor axis approaches R then c approes iR !
 
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This site is turning me down.c'mon guys!its not a hard problem!I mean I may not be able to do it but guys who go to the university must be able to!
 
It's easiest to just solve the poissons equation.
Not sure what alternate method you are suggesting here.
I thought you could only get the field on the symmetry axis without poissons?
 
Let me clear it up.by integration we can simply get the potential of a rod with uniform charge density in space.putting its potential CONST and then doing some algebra we find out its equipotentials are ellipses whose centers are at the edge of the rod(in 2D.in 3D its just ellipses rotated about the rod,i think they call'em ellipsoids).
so if we have a conducting ellipsoid,it means that we we have an ellipsoid at a CONSTANT potential>>so we simply forget about the ellipsoid and put a rod instead.in analogy with what we prooved we can simply find out a rod of what length and charge per length will do the job.
so we have the potential of an ellipsoid in space!(we use the potential of rod except that we right its landa and lenght(L) in terms of V of the conductor and its sami major axis).
now a disk is an ellipsoid really.(in the limit that its z length is zero.)
now we just have to take a limit of what we find for a rod to get the potential of disk in space.but it gets TRICKY!mathematically!
 
Sounds like a steange way to go at it, why not just brute force integrate it with the free space green function?
 
its simple!the final answer is going to come up simple.and the brute force way is HARD!
but we have the potential.we just need to plug in the according prameters!which is much simpler then doing the BRUTE FORCE integral which can't be done!
 
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