Axial vs Equatorial Field

Axial point: lies on the line through the center of the dipole, along its axis (extending the N-S line).

Equatorial point: lies on the perpendicular bisector of the dipole at the center.

Axial field is PARALLEL to the dipole moment; equatorial field is ANTIPARALLEL.

B_axial = (μ₀/4π)·(2m·r)/(r² − L²)². For r ≫ L: B_axial → (μ₀/4π)·(2m/r³).

B_equatorial = (μ₀/4π)·m/(r² + L²)^(3/2). For r ≫ L: B_equatorial → (μ₀/4π)·(m/r³).

Ratio at same r: B_axial / B_equatorial = 2 (for short dipoles).

Direction of axial field: from S to N of the source dipole (same as m).

Direction of equatorial field: opposite to m (from N to S externally).