- Resistance is inversely proportional to the square of the radius (R ∝ 1/r²), assuming constant length and material. - When conductors are in series, their resistances add up (R_total = R1 + R2 + ...).
Two metallic wires made from copper have same length but the radius of wire 1 is half of that of wire 2. The resistance of wire 1 is R. If both the wires are joined together in series, the total resistance becomes
Asked in UPSC CDS 1 2018 · Topic: Conductivity (Electrical Conductivity and Resistivity: Definitions, Units, and Ohm's Law)
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