Potential energy for electrostatic forces between two bodies




The electrostatic force exerted by a charge Q on another charge q separated by a distance r is given by Coulomb's Law

where is a vector of length 1 pointing from Q to q and ε0 is the vacuum permittivity. This may also be written using Coulomb constant ke = 1 ⁄ 4πε0.

The work W required to move q from A to any point B in the electrostatic force field is given by the potential function

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