How many times the resistance of an iron wire 1 m long is greater than the resistance of a copper

How many times the resistance of an iron wire 1 m long is greater than the resistance of a copper wire of the same length and with the same cross-sectional area.

Given:

S1 = S2 = S – the cross-sectional area of both conductors is the same;

l1 = l2 = 1 meter – the length of the conductors;

r1 = 0.098 Ohm * mm ^ 2 / m – iron resistivity;

r2 = 0.017 Ohm * mm ^ 2 / m – copper resistivity.

It is required to determine R1 / R2 – how many times the resistance of the iron wire is greater than that of copper.

The resistance of the iron wire is:

R1 = r1 * l / S1 = 0.098 * 1 / S = 0.098 / S.

Copper wire resistance is:

R2 = r2 * l / S2 = 0.017 * 1 / S = 0.017 / S.

Then:

R1 / R2 = 0.098 / S / (0.017 / S) = 0.098 / 0.017 = 5.8 times.

Answer: the resistance of an iron conductor is 5.8 times greater than a copper one.