Jackson Problem 3.12/3.18 -- Electric potential near two plates

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To solve the problem similar to Jackson 3.18, where one plate is grounded and the other has potential V, it's essential to adjust the boundary conditions for the function Z(z) compared to problem 3.12. The solution involves using the Green function as indicated in problem 3.17, which facilitates finding the potential in the volume. The Bessel function solution from problem 3.12 provides a partial answer, but additional steps are necessary to account for the new configuration. Understanding the changes in boundary conditions is crucial for completing the solution. Proper application of equation 1.44 will yield the required potential.
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Homework Statement


I need to solve a problem like Jackson 3.18. I need to find potential due to the same configuration but the position of two plates is opposite i.e. Plate at Z=0 contains disc with potential V and plate at Z=0 is grounded.

Homework Equations

The Attempt at a Solution


I think solution of problem 3.12 gives half of the solution as the value of potential in terms of bessel solution. But, i can't figure out what additional things must be done to complete this problem in addition to problem 3.12.
 

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Hello, and welcome to PF!

You need to reconsider the function Z(z). The boundary condition for this function changes when going from prob. 3.12 to prob. 3.18.
 
This is a straightforward application of the result of problem 3.17, once you have the Green function, then simple application of equation 1.44 gives you the potential in the volume.
 
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