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The resistance of a wire of length l and area of cross-section a is x ohm. If the wire is stretched to double its length, its resistance would become:

Options

  1. A2 x ohm
  2. B0.5 x ohm
  3. C4 x ohm
  4. D6 x ohm

Correct answer

C. 4 x ohm

Step-by-step solution

Resistance is directly proportional to length(1) r 1, r 1 / a wire is stretched to double its length the resistance will become r 1, r 1 / a / 2 Combining these two r 41 / a

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