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Question
Two wires of the same material and same length have radii 1 mm and 2 mm respectively. Compare their specific resistance.
Solution
`ρ_1 = ("R"_1 1/(pir_1^2))/l_1`
`ρ_2 = ("R"_2 1/(pir_2^2))/l_2` or
l1 = l2 and R1 = R2
∴ Ratio of resistivity = 1 : 1
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