1785Reputable sourceWell documented
Coulomb's Law of Electric Force
On the timeline · around 1785 ·
What happened
In 1785 the French physicist Charles-Augustin de Coulomb used a delicate torsion balance to measure the force between electric charges. He found that it follows an inverse-square law, just like gravity: the force weakens with the square of the distance between the charges.
Why it matters
Coulomb's law put the study of electricity on a precise mathematical footing and became a foundation of the theory of electromagnetism. The unit of electric charge, the coulomb, is named in his honour.