1. The problem statement, all variables and given/known data I recently encountered a problem wherein I was asked to calculate the potential difference between two non conducting concentric spherical shells of radii R1 and R2. 2. Relevant equations ΔV=-∫E.dr 3. The attempt at a solution While I was able to calculate the potentials of individual spheres due to the other's electric field, I could not understand why, in the solution, an extra term in each sphere's potential was mentioned. The extra term was KQ/R (Where Q=charge of the sphere in consideration and R=its Radius). I later understood that the term can be indirectly called Self Potential (like we have self energy). But How can we calculate the self potential?