Study of the displacement of floating diamagnetic bodies by a magnetic field

Abstract

The authors analyzed the motion of diamagnetic bodies that float on diamagnetic liquids. The motion was inspired by the deformation of the diamagnetic liquid surface by a magnetic field, called the ‘Moses effect’. The influence of the surface tension on the shape of the well pushed out by the steady magnetic field (B ≅ 0·35T) acting on the surface of the liquid was studied both experimentally and theoretically for water, silicone oil and aqueous surfactant solution. The suggested mathematical approach accurately predicted the shape of the well, depending on the surface tension of the liquid. Qualitative analysis is reported regarding the motion of floating diamagnetic polymers and metallic objects driven by the Moses effect. The impact of the bulk magnetic force on the motion is minor for all of the studied diamagnetic rafts. The influences of gravity and interfacial forces on the displacement of rafts may be of a comparable order of magnitude.