Coulomb was born in Angoulême, France. He chose the profession of military engineer, and spent three years, to the decided injury of his health, at Fort Bourbon, Martinique. Upon his return, he was employed at La Rochelle, the Isle of Aix and Cherbourg. He discovered an inverse relationship on the force between charges and the square of its distance.
Coulomb is perhaps most famous for the law of physics bearing his name. Coulomb's law (Equation 1) describes the relationship between force, charge and distance. In 1785, Coulomb published a paper describing the torsion balance. This paper would become the first of a series of seven papers that Coulomb would have published on the topics of magnetism and electricity. The torsion balance allowed Coulomb to make more precise measurements of force than anyone prior to that time. Several other researchers, including Henry Cavendish, Joseph Priestly, and Charles Stanhope were similar work related to electrostatics. In fact, independently Henry Cavendish had determined experimentally the electric force was an inverse square law around the same time. However Cavendish never published his results or experiments, so it was not until 1879 that this fact was discovered by James Maxwell. While Priestly's work with electrical repulsion served as the basis for Coulomb's research.
Coulomb was also the first to show that the force of friction is always proportional to the pressure exerted at 90° to the surface. His experiments with electricity, using a sensitive apparatus called the torsion balance, showed that the force between two charges displays inverse variation with respect to the square of the distance between the charges and direct variation with respect to the product of their size (mathematically the same as the law of gravity).