Charles Augustin de Coulomb was the French physicist who experimentally verified the inverse square law of electrostatic force. Although Coulomb worked on many areas of science, for instance examining the relationship between pressure and friction, it is his work on electrostatics for which he is best remembered. Using a torsion balance that he invented to measure extremely small forces (with magnitudes as small as 
he developed his 'fundamental law of electricity' (now called Coulomb's law). He went on to demonstrate that the same form of law also applied to magnetic forces, although he and his contemporaries insisted that electricity and magnetism were fundamentally different types of force. Coulomb's inverse square law of electrostatic force resulted in the definition of electric charge, the SI unit of which is named in his honour.
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