A system of electrical units formerly used in the c.g.s. system (see c.g.s. units). The e.m.u. of electric current is the abampere (all e.m.u. have the prefix ab- attached to the names of practical units). The abampere is the current that, flowing in an arc of a circle (1 centimetre in diameter), exerts a force of 1 dyne on unit magnetic pole at the centre of the circle. In e.m.u. the magnetic constant is of unit magnitude. The system has now been replaced by SI units for most purposes. Compare electrostatic units; Gaussian units; Heaviside–Lorentz units.
Subjects: Chemistry — Physics.