2026 · Q17
Which one among the following statements regarding the electrical resistivity of a conducting wire is correct?
General KnowledgePhysics
- AThe resistivity of the conductor increases if the length of the wire is increased.
- BThe resistivity of the conductor decreases if the length of the wire is increased.
- CThe resistivity of the conductor remains the same if the length of the wire is changed.
- DThe resistivity of the conductor increases if the cross-sectional area of the wire is increased.
Explanation
Electrical resistivity is an intrinsic property of the conductor's material (and temperature), not of its geometry. While resistance R = rho-L/A changes with length and cross-sectional area, the resistivity rho itself is unaffected by changing the wire's dimensions. Increasing length or area therefore leaves resistivity unchanged. Hence option C is correct.