ELECTRIC FIELD AND ELECTRIC FIELD LINES

Coulomb's law describes the force between two charges but does not explain how that interaction is actually transmitted through empty space between them -- historically this puzzle was called 'action at a distance'. Michael Faraday resolved it by proposing the concept of a field: every electric charge modifies the space around itself, creating an electric field that fills the surrounding region, and any second charge brought into that field interacts locally with the field at its own location, and consequently feels a force. Both electric and gravitational interactions are non-contact forces, so the field concept is essential in both cases to explain how the force is actually communicated across empty space. This section develops the electric field first for a single point charge and for systems of point charges, t …