When we explain about an isolated conducting sphere, we have to say that the whole present charge must accumulate on the surface, and in an extremely uniform way, by the symmetry of the sphere. In case the total charge on the sphere is equivalent to Q, the force on a point charge q at a distance r from the center of the sphere should be exactly equal to the force that would produce a point charge Q at the center of that sphere. reelcraft DP5450 OLP
In this way, the electric field created by the sphere is equal to the field produced by a point load Q with a radial component determined by a specific equation. Thus, the electric potential energy that will certainly present a point charge q when placed on the sphere surface will be determined by the equation U = q \ V, where V is the potential difference between a point on the sphere surface and a point in infinity, where the sphere can no longer produce any potential energy in charge q. To perform the calculation, the definition of the potential difference must be applied, using an integration path that follows the radial direction of the field lines.