A metal wire of length l and diameter d has a resistance R. What would be the resistance of another wire of the same metal and of same length but having double the diameter ?

Asked in UPSC CDS 2 2022 · Topic: Conductivity (Electrical Conductivity and Resistivity: Definitions, Units, and Ohm's Law)

1. R
2. R/4
3. R/2
4. 2R

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