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When a conductor is stretched and its length grows by x%, the resistance rises by 2x%. This holds true only if x is less than 10%.

1. The resistance does not change
2. The resistance grows by x%
3. The resistance grows by 2x%
4. The resistance reduces by x%

Correct answer: The resistance grows by 2x%

Solution

When a conductor is stretched, its length increases, and its cross-sectional area decreases, keeping the volume constant. Resistance is directly proportional to the square of the length increase, leading to a 2x% increase in resistance for a small x%.

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