charge, in electricity, property of matter that gives rise to all electrical phenomena. The basic unit of charge, usually denoted by e, is that on the proton or electron; that on the proton is designated as positive (+e) and that on the electron is designated as negative (-e). All other charged elementary particles have charges equal to +e, -e, or some whole number times one of these, with the exception of the quark, a particle whose charge is 1/3e or 2/3e. Every charged particle is surrounded by an electric field of force such that it attracts any charge of opposite sign brought near it and repels any charge of like sign. The magnitude of this force is described by Coulomb's Law. This force is much stronger than the gravitational force between two particles and is responsible for holding protons and electrons together in atoms and in chemical bonding. Any physical system containing equal numbers of positive and negative charges is neutral. Charge is a conserved quantity; the net electric charge in a closed physical system is constant. Although charge is conserved, it can be transferred from one body to another. Electric current is the flow of charge through a conductor.

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