. C OULOMB ’ S L AW Coulomb’s law is a quantitative statement about the force between two point charges. When the linear size of charged bodies are much smaller than the distance separating them, the size may be ignored and the charged bodies are treated as point charges . Coulomb measured the force between two point charges and found that it varied inversely as the square of the distance between the charges and was directly proportional to the product of the magnitude of the two charges and acted along the line joining the two charges .
Thus, if two point charges q , q are separated by a distance r in vacuum, the magnitude of the force ( F ) between them is given by F k ( . ) How did Coulomb arrive at this law from his experiments? Coulomb used a torsion balance * for measuring the force between two charged metallic * A torsion balance is a sensitive device to measure force. It was also used later by Cavendish to measure the very feeble gravitational force between two objects, to verify Newton’s Law of Gravitation.