The electrostatic system of units is used to measure electrical quantities of electric charge, current, and voltage within the centimeter gram second (or "CGS") metric system of units. In electrostatic units, electric charge is derived from Coulomb's Law (expressing the force exerted between two charged particles separated by a distance) by solving for electric charge and setting the constant of proportionality (k_s) equal to unity. Thus, in electrostatic units, the dimensionality of electric charge is derived from the base CGS quantities of length, mass, and time.
