Magnetic Field Inside a Conductor

The magnetic field inside a conductor with uniform current density J = I/πR2 can be found with Ampere's Law.

Inside the conductor the magnetic field B increases linearly with r. Outside the conductor the magnetic field becomes that of a straight conductor and decreases with radius. Note that the expressions for inside and outside would approach the same value at the surface if the magnetic permeability were the same.


Magnetic field concepts

Currents as magnetic sources
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