Medición de la susceptibilidad magnética de sustancias líquidas en el laboratorio de física

Abstract

Measurements of the magnetic susceptibility of the non-ionized water are reported. A simple experiment based on the interaction of a magnet with the substance, measured by an analytical balance, was employed. A NdFeB permanent magnet, which has a magnetic moment \mbox{$m = $0.58 $\pm $ 0.04 A$\cdot $m$^{2}$} was used. A mean value for the bulk susceptibility of the non-ionized water of $\chi$ (-6.8 $\pm $ 0.4) $\times$ 10$^{ - 4}$ (SI) was obtained, by using a theoretical model for the interaction between a dipole and a cylindrical sample. It is also demonstrated that a semi-infinite model is not a good description of the used experimental geometry. This is an experiment easy to be implemented into the basic physics laboratory, for the determination of magnetic susceptibilities of liquid substances.