Remarks: (1)The two expressions Vpdr', W=l/E0e are both ok, and can apply to different situations (2 ) The energy is actually stored in the electric field e or instance, at the points where p=0, but Et0, so the lere are still energy Example. an isolated spherical conductor of radius r and carrying a charge Q. the energy stored is Edi Q IR EO 4丌2r 24丌∈0r QV=CV 4丌02