In terms of the Gaussian base units, it is That is, it is defined so that the proportionality constant in Coulomb's law using CGS-ESU quantities is a dimensionless quantity equal to 1.
Coulomb's law in the CGS-Gaussian system takes the form
This serves to define charge as a quantity in the Gaussian system.
[1] Substituting F = 1 dyn, qG1 = qG2 = 1 statC, and r = 1 cm, we get: From this it is also evident that the quantity dimension of electric charge as defined in the CGS-ESU and Gaussian systems is M1/2L3/2T−1.
The most common cases are:[2] The symbol "≘" ('corresponds to') is used instead of "=" because the two sides cannot be equated.