Which one among the following statements regarding the electrical resistivity of a conducting wire is correct?
A.The resistivity of the conductor increases if the length of the wire is increased.
B.The resistivity of the conductor decreases if the length of the wire is increased.
C.The resistivity of the conductor remains the same if the length of the wire is changed.✓ Correct
D.The resistivity of the conductor increases if the cross-sectional area of the wire is increased.
Explanation
Electrical resistivity (ρ) is an intrinsic property of a material that depends only on the nature of the material and its temperature, not on the geometry (length or cross-section) of the wire. Resistance R = ρL/A depends on length and area, but resistivity itself is unchanged when length or cross-sectional area is altered. Therefore, changing the length of the wire does not change its resistivity — option (c) is correct.
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