Resistance of wire R=ρAl Means R∝Al=πr2l According to the question when l and R are doubled ∴R1∝π(2r)22l⇒R1∝21R Here specific resistance of wire is independent of geometry wire so it depends on the material of wire.
The electric resistance of a certain wire of iron is R. If its length and radius are both doubled, then:
Held on 30 Apr 2004 · Verified 9 Jul 2026.
the resistance will be doubled and the specific resistance will be halved
the resistance will be halved and the specific resistance will remain unchanged
the resistance will be halved and the specific resistance will be doubled
the resistance and the specific resistance, both will remain unchanged
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