# Conductance, electrical

Glossary Definition for 16-19

## Description

The electrical conductance of a component in an electric circuit is a property of a component that describes how the electric current in the component is related to the electrical potential difference (voltage) across it. The greater the electrical conductance, the larger the current for a given potential difference, and the smaller the potential difference, for a given current.

Electrical conductance is usually represented by the symbol *G*.

Electrical conductance is defined, for some component, by the equation

*G* = *I**V*

where *V* is the electrical potential difference across the component and *I* the corresponding electric current.

## Discussion

Conductance is simply the reciprocal of resistance.

## SI unit

siemens, S

## Expressed in base units

kg^{-1} m^{-2} s^{3} A^{2}

## Other commonly used unit(s)

mho (1 mho = 1 Ω^{-1} = 1 S)

## Mathematical expressions

Conductance is related simply to resistance as

*G* = *1**R*

The conductance of a component is related to the electrical conductivity, *σ*, of the material from which the component is made, by

*G* = *σ A**L*

where *A* is the component’s cross-sectional area and *L* is its length.