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Wire of a certain material is stretched slowly be dep10. Its new resistance and specific resistance becomes respectively.

1. Both remain same
2. 1.1 times in both
3. 1.2 times, 1.1 times
4. 1.21 times, same

Correct answer: 1.21 times, same

Solution

When a wire is stretched slowly, its volume is taken as constant, so its length increases and cross-sectional area decreases. Resistance depends on geometry, so it increases, but specific resistance (resistivity) is a material property and remains unchanged.

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