Determine the specific resistance of a conductor with a length of 9 m and a diameter of 1 mm2, if it is known

Determine the specific resistance of a conductor with a length of 9 m and a diameter of 1 mm2, if it is known that at a voltage of 18 V, a current strength of 1.5 A.

L = 9 m.

d = 1 mm.

U = 18 V.

I = 1.5 A.

ρ -?

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

ρ = R * S / L.

S = п * d2 / 4.

ρ = R * п * d2 / 4 * L.

We express the resistance of the conductor R from Ohm’s law for a section of the circuit: R = U / I.

The resistivity of the conductor ρ will be determined by the formula: ρ = U * п * d^2 / 4 * L * I.

ρ = 18 V * 3.14 * (1 mm) ^2/4 * 9 m * 1.5 A = 1.05 Ohm * mm2 / m.

Answer: the resistivity of the conductor is ρ = 1.05 Ohm * mm2 / m.