Statcoulomb

The statcoulomb ($statC$) or franklin ($Fr$) or electrostatic unit of charge ($esu$) is the physical unit for electrical charge used in the centimetre-gram-second system of units (cgs) and Gaussian units. It is a derived unit given by $1\ statC = 1\ g\ cm\ s = 1\ erg\ cm$. The SI system of units uses the coulomb (C) instead. The conversion between C and statC is different in different contexts. The number 2997924580 is 10 times the value of the speed of light expressed in meters/second, and the conversions are exact except where indicated. The coulomb is an extremely large charge rarely encountered in electrostatics, while the statcoulomb is closer to everyday charges.