Calculateur de Densité de Courant Gratuit
Calculez la densité de courant dans un conducteur. Déterminez le courant par unité de section transversale.
Current Density
4,000,000 A/m²
Current Density vs Current
Formule
Current Density
Current density describes how much current flows through a unit area of a conductor.
Formula
J = I / A
where I is the current and A is the cross-sectional area of the conductor. High current density causes excessive heating.
Exemple Résolu
10 A through a wire with 2.5 mm² cross-section.
- 01J = I / A
- 02J = 10 / 2.5 mm²
- 03J = 4 A/mm²
- 04J = 4,000,000 A/m²
Questions Fréquentes
What is a safe current density for copper wire?
For continuous operation, copper wire should typically not exceed about 4 to 6 A/mm². Higher densities cause excessive heating.
Why does current density matter?
Current density determines resistive heating in the conductor. Exceeding safe limits can melt insulation or cause fires.
Is current density uniform across a wire?
At DC, yes. At high AC frequencies, the skin effect causes current to concentrate near the wire surface, increasing effective current density.
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