Electric Field Question

joker_900

1. The problem statement, all variables and given/known data
A large and otherwise plane conducting sheet has on it a hemispherical conducting boss. It is placed in an electric field which, in the absence of theboss, would be uniform, normal to the sheet and of magnitude E. Show that the electric field at point P (the highest point on the boss from the sheet) is 3E.




3. The attempt at a solution

Well I think you're supposed to use a dipole field for this, as I know a sphere in a uniform field develops an electric dipole moment and this seems similar. But I don't really know how to progress. I don't really want a full solution, I would just be grateful if someone gives me a start. Thanks