How many meters of copper wire with a cross section of 2 mm² do you need to take

How many meters of copper wire with a cross section of 2 mm² do you need to take so that its resistance is equal to 1 Ohm?

1. Let’s translate given in the SI system:
Ssection = 2.0 mm² = 2.0 * 10-6 m²
2. 2. Let’s write down the expression to determine the resistivity of the wire:
ρsp = R * Ssech / l, where R is the resistance of the wire, l is the length of the wire, Ssech is the cross-sectional area.
3. Let us express l from here:
l = R * Ssec / ρsp
ρsp of copper is determined according to the reference book 1.7 * 10-8 Ohm * m
4. Substituting the numerical values, we have:
l = R * Ssection / ρsp = 1 * 2 * 10-6 / 1.7 * 10-8 = 117 m
Answer: You need to take 117 meters of copper wire.