1. The problem statement, all variables and given/known data Grounded conductive spherical shell is given. Radius R. Charge is held in d and (-d). d>R. as in the pic. What is the force on the right charge? 2. Relevant equations F=q*q/r^2 3. The attempt at a solution I thought it's just F=(q^2)/(4d^2). Why it's wrong? the right answer is marked. Tnx.