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Question
What happens to the resistance as the conductor is made thicker?
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Solution
The resistance of a conductor is inversely proportional to its area of cross-section, i.e.R α 1 / A. So when the conductor is made thicker, its resistance decreases.
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| Electrical resistivity of some substances at 20°C | ||
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| Electrical resistivity of some substances at 20°C | ||
| − | Material | Resistivity (Ω m) |
| 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 | |
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