Question

Equal potentials are applied on an iron and copper wire of same length. In order to have the same current flow in the two wires, the ratio r (iron)/r(copper) of their radii must be (Given that specific resistance of iron =1.0 xx 10^(-7) ohm-m and specific resistance of copper =1.7 xx 10^(-8) ohm-m)

Answer 1

the ans is approximately 2.5