How much copper is required for a wire 10 km long, the resistance of which should be 10 Ohm

How much copper is required for a wire 10 km long, the resistance of which should be 10 Ohm, if the copper density p (po) = 8.5 g / cm2

Data: l (wire length) = 10 km; R (required resistance) = 10 ohms.

Reference values: ρ (resistivity of copper, n.o.) = 0.017 Ohm * mm2 / m; according to the condition ρm (copper density) = 8.5 g / cm3 = 8500 kg / m3.

SI: l = 10 km = 10 * 10 ^ 3 m.

1) Wire cross-sectional area: R = ρ * l / S and S = ρ * l / R = 0.017 * 10 * 10 ^ 3/10 = 17 mm2 = 17 * 10 ^ -6 m2.

2) The volume of copper wire: V = S * h = 17 * 10 ^ -6 * 10 * 10 ^ 3 = 0.17 m3.

3) The mass of copper for the manufacture of wire: m = ρm * V = 8500 * 0.17 = 1445 kg.