Conductance:- The reciprocal of the resistance is called as the conductance and is represented by G. As the resistance is defined as the opposition offered by the conductor to the flow of current, so the conductance is defined as the inducement which the conductor offers to the flow of current.
The unit of conductance is mho and is represented as ℧.
SpecificConductance:- As the reciprocal of a resistance is called conductance, similarly the reciprocal of specific resistance is called specific conductivity or conductance and may be defined as the conductance between opposite faces of a unit cube. The units in which it is measured is mho-cm. From equation (2)
Circular Mil:- The cross-sectional area used above is represented in square cm, or square inch etc. If the conductor is of circular section its area = π (d 2/4) sq. inch, where d is the diameter of the conductor in inches.
If the conductor is of rectangular section its area=length x breadth. In America there is another way of representation of area known as Circular Mil or Square Mil.