Resistance of a conductor with uniform cross-section is given by,
R=ρAl
In this case the cross-sectional area is π(b2−a2).
Therefore,
R=ρπ(b2−a2)l=3.14×[(42−22)×10−6](2.4×10−8)×3.14=2×10−3Ω
Hence, n=2.
JEE Main 2023 — Physics Electromagnetism
A hollow cylindrical conductor has length of 3.14m, while its inner and outer diameters are 4mm and 8mm respectively. The resistance of the conductor is n×10−3Ω.
If the resistivity of the material is 2.4×10−8Ωm. The value of n is _____.
Held on 24 Jan 2023 · Verified 6 Jul 2026.
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