1. The problem statement, all variables and given/known data If the inner sphere of radius a has charge +Q and the outer sphere of radius b has charge -Q/2. What's the electric field between them? 3. The attempt at a solution If I use Gauss' law then I would have E*4*pi*a^2 = Q/ε then just solve for E. Is that correct? It seems like the outer sphere would affect the E-field on the inner sphere. By the way, they don't say that these are conducting spheres. Thanks for any help.