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The resistivity of a wire

1. Increases with the length of the wire
2. Decreases with the area of cross-section
3. Decreases with the length and increases with the cross-section of the wire
4. None of the above statement is correct

Correct answer: None of the above statement is correct

Solution

Resistivity depends on the nature of the material and temperature, not on the length or cross-sectional area of the wire. Therefore, all three statements about dependence on length and area are incorrect.

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