Calculate the resistivity of copper, a wire of which is 500 m long and has a cross-sectional area of 0.1 mm2

Calculate the resistivity of copper, a wire of which is 500 m long and has a cross-sectional area of 0.1 mm2 and has a resistance of 85 ohms.

Task data: l (length of the wire used) = 500 m; S (cross-sectional area) = 0.1 mm2; R (wire resistance) = 85 ohms.

The desired resistivity of copper can be expressed from the formula: R = ρ * l / S, whence ρ = R * S / l.

Let’s calculate: ρ = 85 * 0.1 / 500 = 0.017 Ohm * mm2 / m.

Answer: The specific resistance of copper, according to the calculation, is 0.017 Ohm * mm2 / m.