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Q138 (NDA-I/2025) NA › NA

If the length of a copper wire is increased by twice, then its resistivity will be

Result
Your answer:  ·  Correct: C
Explanation

Resistivity (ρ) is an intrinsic property of a material. It depends only on the nature of the material and its temperature.

  • Resistance (R) depends on the dimensions of the object (length and cross-sectional area) according to the formula R = ρL/A.
  • Resistivity (ρ) is independent of the shape, size, length, or thickness of the wire.

Since the wire remains copper and no temperature change is mentioned, the resistivity remains the same, even if the length is increased.

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