The cable consists of two steel conductors with a cross-sectional area of 0.6 mm2 each and four copper

The cable consists of two steel conductors with a cross-sectional area of 0.6 mm2 each and four copper conductors with a cross-sectional area of 0.85 mm2 each. What is the voltage drop for each kilometer of cable at a current of 0.1 A?

The dependence of the resistance of the conductor on its parameters is determined by the formula: R = p * L / S, where:
p is the resistivity;
p copper = 0.017 Ohm * mm ^ 2 / m;
p of steel = 0.13 Ohm * mm ^ 2 / m
L – conductor length
S is the cross-sectional area of the conductor.
Area in sq. m can not be translated, these units of measurement will be reduced.
U = I * R;
Find the resistance of the copper section:
Rm = 0.017 * 1000 / (4 * 0.85) = 5 ohms.
Find the resistance of the steel section:
Rc = 0.13 * 1000 / (2 * 0.6) = 108.33 Ohm.
The total resistances of the circuit R = Rm * Rc / (Rm + Rc) = 5 * 108.33 / (5 + 108.33) = 4.78 Ohm.
U = 0.1 * 4.78 = 0.48 V;