Derived from the Greek for 'work', what is the CGS unit of energy?
Erg is still widely used in astrophysics and sometimes in mechanics. Erg The erg is a unit of energy and work equal to 10 joules. It originated in the centimetre–gram–second (CGS) system of units. It has the symbol "erg". The erg is not an SI unit. Its name is derived from "ergon" (ἔργον), a Greek word meaning "work" or "task". An erg is the amount of work done by a force of one dyne exerted for a distance of one centimeter. In the CGS base units, it is equal to one gram centimeter-squared per second-squared (g·cm/s). It is thus equal to
Gray (unit) Gray (unit) The gray (symbol: Gy) is a derived unit of ionizing radiation dose in the International System of Units (SI). It is defined as the absorption of one joule of radiation energy per kilogram of matter. It is used as a unit of the radiation quantity absorbed dose which measures the energy deposited in a unit mass at a certain position, and of the radiation quantity kerma, which is the amount of energy that is transferred from photons to electrons per unit mass at a certain position. The corresponding cgs unit to the gray is the rad (equivalent to