MARK AS BRAINLIST COULOMB's Law. Coulomb's law is the law of electrostatic force between electric charges. It is the most important law of electrostatics. From previous page we already know that the charges are of two types that is positive and negative. We also know that opposite charges attract each other and same charges repel each other. This interaction of attraction and repulsion gives rise to a force. This force can be attractive or REPULSIVE, depending on whether the charges we have are of opposite or same in type.So we use Coulomb's Law to measure the amount of electrostatic force acting on the charges. We also use it to find the direction of the force.One more important point to note here is about the range of these forces. These forces ACT over an enormous range. Its range varies from nuclear dimensions (10−15m i.e. of the order of Fermi) to macroscopic DISTANCES as large as 108m. The inverse SQUARE law is valid to a high degree of accuracy over this range of separation.