Point charge

Point charge

In electromagnetism, a point charge is a point particle with a nonzero electric charge. It can also be defined as a charged body or charge carrier whose effective diameter is much smaller than the distance to another charged object. The fundamental equation of electrostatics is Coulomb's law, which describes the electric force between two point charges. Another result, Earnshaw's theorem, states that a collection of point charges cannot be maintained in a static equilibrium configuration solely by the electrostatic interaction of the charges. The electric field associated with a classical point charge increases to infinity as the distance from the point charge decreases towards zero, which indicates that the model is no longer accurate in this limit.