# 16: CGS Electricity and Magnetism

An older system of units, still used by some authors, was the CGS (centimeter-gram-second) system. In this system, a *dyne* is the *force* that will impart an acceleration of 1 cm s^{-}^{2}to a mass of 1 gram. An *erg* is the *work* done when a force of one dyne moves its point of application through 1 cm in the line of action of the force. It will not take the reader a moment to see that a newton is equal to 10^{5} dynes, and a joule is 10^{7} ergs. As far as mechanical units are concerned, neither one system has any particular advantage over the other.