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.
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).
| Resistivity | |
|---|---|
Common symbols | ρ |
| SI unit | ohm metre (Ω⋅m) |
| In SI base units | kg⋅m3⋅s−3⋅A−2 |
Derivations from other quantities | |
| Dimension | |
| Conductivity | |
|---|---|
Common symbols | σ, κ, γ |
| SI unit | siemens per metre (S/m) |
| In SI base units | kg−1⋅m−3⋅s3⋅A2 |
Derivations from other quantities | |
| Dimension | |
https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity
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