 In particular, to circumvent the mathematical challenges of the spatially complex equipotential surfaces within the device, an "average" electrostatic potential experienced by "each" electron is utilized in the derivation.Apparent mathematical differences are understood more fundamentally as the potential energy, formula_37, of an isolated device (self-capacitance) is twice that stored in a "connected" device in the lower limit "N"=1.As "N" grows large, formula_38.