Compute resistivity ρ = R·A / L from measured resistance, cross-section area and length.
由测得的电阻、截面积与长度计算材料电阻率(电导率倒数)。
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Resistivity | rho = R · A / L, where R is resistance, A the cross-section and L the length | ISO 80000-6:2008, Quantities and units - Part 6: Electromagnetism |
| Unit | The SI unit of resistivity is the ohm metre (Ω·m) | ISO 80000-6:2008, Quantities and units - Part 6: Electromagnetism |
| Conductivity | sigma = 1/rho, the reciprocal of resistivity | ISO 80000-6:2008, Quantities and units - Part 6: Electromagnetism |
| Temperature dependence | Metals show an approximately linear rise: rho = rho_0 · ( 1 + alpha · ΔT ) | ISO 80000-6:2008, Quantities and units - Part 6 (temperature coefficient of resistance) |