Calcolatrice Resistenza del Filo Gratuita
Calcola la resistenza di un filo da resistività, lunghezza e sezione.
Ω·m
m
mm²
Wire Resistance
0.6720 Ω
Wire Resistance vs Resistivity (ρ)
Formula
## Wire Resistance The resistance of a wire depends on the material, its length, and cross-sectional area. ### Formula **R = ρ * L / A** where ρ is the resistivity of the material (Ω·m), L is the wire length, and A is the cross-sectional area. Copper has ρ = 1.68 x 10^-8 Ω·m.
Esempio Risolto
100 m of copper wire with 2.5 mm² cross-section.
- 01R = ρ * L / A
- 02R = 1.68e-8 * 100 / 2.5e-6
- 03R = 1.68e-6 / 2.5e-6
- 04R = 0.672 Ω
Domande Frequenti
What is the resistivity of common conductors?
Copper: 1.68e-8, aluminum: 2.65e-8, silver: 1.59e-8, gold: 2.44e-8 (all in Ω·m at 20°C).
How does wire length affect resistance?
Resistance is proportional to length. Doubling the wire length doubles the resistance.
Why use thicker wire for high current?
A larger cross-section reduces resistance and thus reduces I²R heating losses and voltage drops.
Impara