A copper wire with a cross section of 0.03 mm2 and a length of 200 m is wound on the coil of the electromagnet.

A copper wire with a cross section of 0.03 mm2 and a length of 200 m is wound on the coil of the electromagnet. Find the resistance and mass of the winding. The density of copper is 8900 kg / m3.

Initial data: S (wire section) = 0.03 mm2 (0.03 * 10-6 m2); l (copper wire length) = 200 m.

Constants: ρ (specific electrical resistance of copper) = 0.017 Ohm * mm2 / m; by condition ρm (copper density) = 8900 kg / m3.

1) Determine the resistance of the electromagnet winding: R = ρ * l / S = 0.017 * 200 / 0.03 = 113.3 Ohm.

2) Calculate the mass of the winding: m = ρm * V = ρm * l * S = 8900 * 200 * 0.03 * 10-6 = 0.0534 kg (53.4 g).

Answer: The electromagnet winding has a resistance of 113.3 ohms and a mass of 53.4 g.