ampere-turn

. (Elec.) A unit of magnetomotive force equal to the product of one complete convolution (of a coiled conductor) into one ampère of current; thus, a conductor having five convolutions and carrying a current of half an ampère is said to have 21/2 ampère turns. The magnetizing effect of a coil is proportional to the number of its ampère turns. [ Webster 1913 Suppl. ]