resistivity
The electrical resistance of a metre cube of material, constant for a given material at a specific temperature; symbol ?, units ?.m (ohm.metre). At 0°C, for copper (a good conductor), ? = 1·55 × 10?8 ?.m; for germanium (a semiconductor), ? = 0·5 ?.m approximately; for glass (an insulator), ? = 1011?.m approximately. 1/? is conductivity.
Portions of the summary below have been contributed by Wikipedia.
| Material | Resistivity (ohm meters) | Temperature coefficient per kelvin * |
|---|---|---|
| Silver | 1.59 × 10-8 | .0038 |
| Copper | 1.72 × 10-8 | .0039 |
| Gold | 2.44 × 10-8 | .0034 |
| Aluminium | 2.82 × 10-8 | .0039 |
| Tungsten | 5.6 × 10-8 | .0045 |
| Iron | 1.0 × 10-7 | .005 |
| Brass | 0.8 × 10-7 | .0015 |
| Platinum | 1.1 × 10-7 | .00392 |
| Lead | 2.2 × 10-7 | .0039 |
| Manganin | 4.82 × 10-7 | .000002 |
| Constantan | 4.9 × 10-7 | .00001 |
| Mercury | 9.8 × 10-7 | .0009 |
| Nichrome | 1.10 × 10-6 | .0004 |
| Carbon | 3.5 × 10-5 | -.0005 |
| Germanium | 4.6 × 10-1 | -.048 |
| Silicon | 6.40 × 102 | -.075 |
| Glass | 10 | nil |
| Hard rubber | approximately 1013 | nil |
| Sulfur | 1015 | nil |
| Quartz (fused) | 7.5 × 1017 | nil |
| PET | approximately 1 × 1020 | nil |
| Teflon | approximately 1 × 10 | nil |
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