Magnetic Fields for a Pair of Parallel Currents and for a Ring Current
This Demonstration calculates magnetic fields for a pair of oppositely directed parallel currents and also for the cross-section of a ring current passing through the plane. The currents are assumed to be filamentary in either case.
For a pair of parallel currents, the magnetic field pattern depends on the separation distance .
For a ring current, the magnetic field is calculated using a complete elliptic integral. The pattern depends on the ring radius .
In both cases, you can vary the current and length . The magnetic field and energy intensities are indicated by variations in color.