Nickel wire with a length of 1 m and a cross section of 1 mm ^ 2 resists a current of 0.44 ohms.

Nickel wire with a length of 1 m and a cross section of 1 mm ^ 2 resists a current of 0.44 ohms. Calculate the resistance that a 100 m long nickel wire with a cross section of 0.5 mm ^ 2 will have to current.

L1 = 1 m.

S1 = 1 mm2.

R1 = 0.44 ohm.

L2 = 100 m.

S2 = 0.5 mm2.

R2 -?

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

R2 = ρ * L2 / S2.

The specific resistance of the material ρ of the conductor is expressed from the formula: R1 = ρ * L1 / S1.

ρ = R1 * S1 / L1.

R2 = R1 * S1 * L2 / S2 * L1.

R2 = 0.44 Ohm * 1 mm2 * 100 m / 0.5 mm2 * 1 m = 88 Ohm.

Answer: the resistance of the nickel wire will be R2 = 88 ohms.