Coulomb force's direction is along the connecting line, like charges repel each other and like charges attract each other.
The magnitude of the interaction force between Q 1 and Q2 at two stationary points of coulomb force in vacuum is directly proportional to the product of Q 1 and Q2, and inversely proportional to the square of the distance R.
French physicist Charles Coulomb discovered it in 1785, hence the name of a physical law. Coulomb's law is the first quantitative law in the history of electricity development. Therefore, the study of electricity from qualitative to quantitative stage is an important milestone in the history of electricity.