What is the strength of the current passing through an iron conductor 6 m long and with a cross-sectional

What is the strength of the current passing through an iron conductor 6 m long and with a cross-sectional area of 0.05 mm2 when the voltage at the ends of the conductor is 12 V?

l = 6 m.

S = 0.05 mm ^ 2 = 0.05 * 10 ^ -6 m ^ 2.

U = 12V.

ρ = 1 * 10 ^ -7 Ohm * m.

I -?

We express the current strength in the conductor I according to Ohm’s law for the section of the circuit: I = U / R, where U is the voltage at the ends of the conductor, R is the resistance of the conductor.

The resistance R of a uniform cylindrical conductor is determined by the formula: R = ρ * l / S, where ρ is the specific resistance of the substance from which the conductor is made, l is the length of the conductor, S is the cross-sectional area of the conductor.

I = U * S / ρ * l.

I = 12V * 0.05 * 10 ^ -6 m ^ 2/1 * 10 ^ -7 Ohm * m * 6 m = 1 A.

Answer: the current in the iron conductor is I = 1 A.