1. The problem statement, all variables and given/known data I was looking for some practice problems in my textbook and found this problem that I was just a little stuck on. I drew the diagram from my textbook with the givens of the problem. 2. Relevant equations ∲E*dA = Q (inside) / ɛ0 3. The attempt at a solution For r less than/equal to a: E(4pir^2) = 3Q/ɛ ---> E = 3Q / 4*pi*ɛ(r^2) For a<r<b: E= -5Q/ (4*pi*r^2) Can somebody verify with me that I've done the first two above correctly? Also the part that I got stuck on was the r is greater than/equal to c... I see that if r was equal to c there would be no charge, hence e-field will be zero inside the conductor. However, when r is greater than c, then there would be a charge of -5Q. How would I usually deal with the case of "greater than/equal to"? Thank you Physics community!