1. The problem statement, all variables and given/known data A solid conducting sphere with radius of R1 and charge of 3Q, is placed in the center of a thin conducting spherical shell with inner radius of R2 and outer radius of R3, charged with -Q what is the field for r<R1, R2>r>R1, R3>r>R2, r>R3 and what is the charge distrubution for the sphere and the shell? Well I'm quite sure that the field inside the sphere is 0, and when R2>r>R1 the field is like of a 3Q point charge in the middle of the sphere. and also when r>R3 it's the field of a point charge 2Q in the middle of the sphere. but what hapeens in R3>r>R2? Although this segment describes points inside the conducting shell I don't think the field is 0... but I don't know if I'm right because you always have to assume that the field inside a conductor is 0 right? (under electro-static conditions). Also what is the charge distrubution? How can I know it? I know that inside the sphere all the charge will be on the surface... but what happens with respect to the 2-surfaced shell?