The magnitude of the electrostatic force of attraction or repulsionbetween two point charges is directly proportional to the product ofthe magnitudes of charges and inversely proportional to the square of thedistance between them. The force is along the straight line joining them.If the two charges have the same sign, the electrostatic force betweenthem is repulsive, if they have different signs, the force between themis attractive. In the equilibrium stateholds even within atoms, correctlydescribing the force between the positively charged atomic nucleus andeach of the negatively charged electrons. This simple law also correctlyaccounts for the forces that bind atoms together to form molecules andfor the forces that bind atoms and molecules together to form solids andliquids. Generally, as the distance between ions increases, the force ofattraction, and binding energy, approach zero and ionic bonding is lessfavorable. As the magnitude of opposing charges increases, energy increasesand ionic bonding is more favorable. Coulomb's law, or Coulomb's inversesquarelaw, is an experimental law of physics that quantifies the amount offorce between two stationaries, electrically charged particles. The electricforce between charged bodies at rest is conventionally called electrostaticforce or Coulomb force. The quantity of electrostatic force betweenstationary charges is always described by Coulomb's law. The law was firstpublished in 1785 by French physicist Charles-Augustin de Coulomb, andwas essential to the development of the theory of electromagnetism, maybeeven its starting point, because it was now possible to discuss quantity ofelectric charge in a meaningful way.