As we have resistance (R), we also have the reciprocal of resistance i.e. conductance (G=1/R). Unit of resistance is the ohm and the unit of conductance is mho.
As we have reactance (X), we also have the reciprocal of reactance i.e. susceptance (B=1/X). Unit of reactance is ohm and the unit of susceptance is siemens.
As we have an impedance (Z), we also have the reciprocal of impedance i.e. admittance (Y=1/Z). Unit of impedance is ohm and the unit of admittance is siemens.
We can say that as resistance is the real part and reactance is the imaginary part of the impedance. In the same manner, conductance is the real part and susceptance is the imaginary part of the admittance.
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