Case 1. You have a sphere with Radius R and middle point X with the charge Q. The charge is equally distributed over the sphere. for E(X,r) = 0 for r_1 < R, E inside the sphere is 0. If r_2 > R then E ≠ 0 ; but let's say E(X,r_2) := w If you put all the charge of the sphere into X then, it would still be E(X,r_2) = w Why is that so? I could imagine that, if you had r_1 << R, but I found it first without the special case that R a lot larger than r_1 Where can I get information about that? Case 2. Now the charge is no longer equally distributed over the sphere. Then E(X,r_1) is no longer 0. But what happens with E(X, r_2) ? My guess is, that E = w, because in case 1 it didn't matter, if you viewed the sphere as a sphere or as a point. However I can't say for sure. Can someone plz help me?