- The resistance (R) of a wire is given by the formula R = ρ (L/A), where ρ is the resistivity, L is the length, and A is the area of cross-section. - While the resistance (R) of the copper wires will be different because they have different lengths and diameters, their resistivity (ρ) will be the same because they are all made of the same material (copper) and are presumably at the same temperature.
We are given three copper wires of different lengths and different areas of cross-section. Which one of the following would have highest resistivity ?
Asked in UPSC CDS 1 2021 · Topic: Conductivity (Electrical Conductivity and Resistivity: Definitions, Units, and Ohm's Law)
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