Question -
Answer -
| Material | Resistivity |
| Conductors | Silver | 1.60 × 10–8 |
| Copper | 1.62 × 10–8 |
| Aluminium | 2.63 × 10–8 |
| Tungsten | 5.20 × 10–8 |
| Nickel | 6.84 × 10–8 |
| Iron | 10.0 × 10–8 |
| Chromium | 12.9 × 10–8 |
| Mercury | 94.0 × 10–8 |
| Manganese | 1.84 × 10–6 |
| Alloys | Constantan | 49 × 10–6 |
| Manganin | 44 × 10–6 |
| Nichrome | 100 × 10–6 |
| Insulators | Glass | 1010 – 1014 |
| Hard rubber | 1013 – 1016 |
| Ebonite | 1015 – 1017 |
| Diamond | 1012 – 1013 |
| Paper (dry) | 1012 |
a. Which among iron and mercury is a better conductor?
b. Which material is the best conductor?
Answer
a. Iron is a better conductor than mercury because the resistivity of mercury is more than the resistivity of iron.
b. Among all the materials listed in the table, silver is the best conductor because the resistivity of silver is lowest among all, i.e., 1.60 × 10–8.