Coulomb’s law says that the electric force between two point charges follows an inverse-square relationship.
The law states that the force is proportional to the product of the two charges and inversely proportional to the square of the distance between them. Like charges repel, while unlike charges attract. In vacuum, the proportionality constant is expressed using the electric constant.
French physicist Charles-Augustin de Coulomb established this relationship in the eighteenth century using torsion-balance experiments. His measurements helped turn electrostatics into a quantitative science and provided a foundation for later electromagnetic theory.
Coulomb’s law resembles Newton’s law of universal gravitation mathematically, but electric forces can attract or repel. The point-charge form is simplest for isolated charges; extended charge distributions require integration or other methods.