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Just as conductance has an opposite  resistance; permeability also has an opposite  reluctance. RELUCTANCE is mathematically the reciprocal of PERMEABILITY. The unit of measurement for reluctance is the REL or OERSTED, and its symbol is Ö. Voltage is the measurement for Amplitude of an electrical circuit. Magnetism also has a counterpart for this, which is called MAGNETOMOTIVE FORCE. Magnetomotive force is the force which produces the magnetic lines of force or FLUX. The unit of magnetomotive force is the GILBERT, and its symbol is G. The formula for finding the value of G is as follows: G = N x I x 1.26 Where: N = the number of turns in the coil I = the current flowing through the coil in Amperes ( N x I is also called AMPERETURNS) 
