# 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;