V. ELECTRO-MAGNETIC UNITS.—
Reading edition
UNIT CURRENT is that which in a wire of unit length, bent so as to form an arc of a circle of unit radius, would act upon a unit pole at the centre of the circle with unit force.
UNIT QUANTITY of electricity is that which a unit current conveys in unit time.
UNIT ELECTRO-MOTIVE FORCE or DIFFERENCE OF POTENTIAL is that which is produced in a conductor moving through a magnetic field at such a rate as to cut one unit line per second.
UNIT RESISTANCE is that of a conductor in which unit current is produced by unit electro-motive force between its ends.
UNIT CAPACITY is that of a condenser which will be at unit difference of potential when charged with unit quantity.
Electric and magnetic force varies inversely as the square of the distance.