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प्रश्न
What would be the effect on the resistance of a metal wire of:
increasing its diameter?
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उत्तर
The resistance of a conductor is inversely proportional to its area of cross-section, i.e. R α 1 / A. So on increasing its diameter, its resistance will decrease.
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| Electrical resistivity of some substances at 20°C | ||
| − | Material | Resistivity (Ω m) |
| Conductors |
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