Convert Ohm circular mil per foot to Ohm-metres
Convert Ohm circular mil per foot (Ω·cmil/ft) to Ohm-metres (Ω·m) instantly and accurately.
Conversion Formula
Ω·m = Ω·cmil/ft × 1.662426113e-9
About Ohm circular mil per foot
The ohm circular mil per foot (Ω·cmil/ft) is the US customary resistivity unit for wires and cables, equal to π×6.4516×10⁻¹⁰/(4×0.3048) Ω·m ≈ 1.66243×10⁻⁹ Ω·m. Copper has resistivity ≈1.012 Ω·cmil/ft; wire tables in NFPA 70 (NEC) and ASTM B3 list conductor resistivity in this unit. 1 Ω·cmil/ft ≈ 1.66243 nΩ·m.
About Ohm-metres
The ohm-metre (Ω·m) is the SI coherent unit of electrical resistivity, equal to 1 V·m/A = 1 kg·m³·A⁻²·s⁻³. Seawater is ≈0.2 Ω·m; deionised water is ~18 MΩ·cm = 180 kΩ·m; silicon carbide ≈0.1-10 Ω·m; IEC 60287 specifies cable insulation resistivity in Ω·m. 1 Ω·m = 10² Ω·cm = 10⁶ µΩ·m.
Quick Reference Table
| Ohm circular mil per foot (Ω·cmil/ft) | Ohm-metres (Ω·m) |
|---|---|
| 1 Ω·cmil/ft | 1.662 × 10-9 Ω·m |
| 2 Ω·cmil/ft | 3.325 × 10-9 Ω·m |
| 5 Ω·cmil/ft | 8.312 × 10-9 Ω·m |
| 10 Ω·cmil/ft | 1.662 × 10-8 Ω·m |
| 25 Ω·cmil/ft | 4.156 × 10-8 Ω·m |
| 50 Ω·cmil/ft | 8.312 × 10-8 Ω·m |
| 100 Ω·cmil/ft | 1.662 × 10-7 Ω·m |