Axial magnetic field of short bar magnet (dipole) (B_axial = (μ₀/4π)(2m/r³) on axis, m = pole strength × 2l)

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B_axial = (μ₀/4π)(2m/r³) on axis, m = pole strength × 2l

What each symbol means

SymbolWhat it stands for
mMagnetic dipole moment (A·m²)
rDistance along axis from center (m)

When to use this

Short dipole / far field on axis; point dipole limit.