# Electrical resistivity and conductivity

**Electrical resistivity** (also called **specific electrical resistance** or **volume resistivity**) is a fundamental property of a material that measures how strongly it resists electric current. Its inverse, called electrical conductivity, quantifies how well a material conducts electricity. A low resistivity indicates a material that readily allows electric current. Resistivity is commonly represented by the Greek letter *ρ* (rho). The SI unit of electrical resistivity is the ohm-meter (Ω⋅m).[1][2][3] For example, if a 1 m solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is 1 Ω, then the resistivity of the material is 1 Ω⋅m.

Resistivity | |
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Common symbols | ρ |

SI unit | ohm metre (Ω⋅m) |

In SI base units | kg⋅m^{3}⋅s^{−3}⋅A^{−2} |

Derivations from other quantities | |

Dimension |

Conductivity | |
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Common symbols | σ, κ, γ |

SI unit | siemens per metre (S/m) |

In SI base units | kg^{−1}⋅m^{−3}⋅s^{3}⋅A^{2} |

Derivations from other quantities | |

Dimension |

**Electrical conductivity** or **specific conductance** is the reciprocal of electrical resistivity. It represents a material's ability to conduct electric current. It is commonly signified by the Greek letter σ (sigma), but κ (kappa) (especially in electrical engineering) and γ (gamma) are sometimes used. The SI unit of electrical conductivity is siemens per metre (S/m).