# Changes: Electrical conductance

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Electrical conductance is the reciprocal of electrical resistance. It is a measure of how easily electricity flows along a certain path through an electrical element. The SI derived unit of conductance is the siemens (formerly referred to as the reciprocal ohm or mho). Oliver Heaviside coined the term in September 1885.

Electrical conductance should not be confused with conduction, which is the mechanism by which charge flows, or with conductivity, which is a property of a material.

## Relation to other quantities

As mentioned, conductance is related to resistance by:

$G = \frac{1}{R} = \frac{I}{V} \,$

for purely resistive circuits

where:

G is the electrical conductance,
R is the electrical resistance,
I is the electric current,
V is the voltage.

(Note: this is not true where the impedance is complex)

Furthermore, conductance is related to susceptance and admittance by the equation:

$Y = G + j B \,$

or

$G = Re(Y) \,$

where:

$j$ is the imaginary unit,