Abstract: Teaching apparatus for demonstrating the effect of a magnetic field on a magnetic moment wherein a pair of electromagnet coils produce a uniform and constant magnetic field in a direction substantially perpendicular to the plane of a surface on which the apparatus is supported, i.e. typically in a vertical direction. In one aspect a spherical insulator with a magnetic dipole imbedded at its center is positioned in the magnetic field and supported on an ultra-low friction air bearing for demonstrating the interaction of magnetic fields with magnetic moments. In another aspect, a magnetic dipole is located in the magnetic field and is suspended by a spring scale to allow direct measurement of translational forces in the presence of a magnetic field gradient. In another aspect, a rotatable magnet produces a uniform magnetic field in a direction substantially perpendicular to the first-mentioned field for demonstrating nutation when the spherical part is spinned and the magnet is rotated.