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Measurement Techniques
9.1. THE SUSCEPTIBILITY BALANCECommonly, for measuring the magnetic susceptibility of samples having the shape of long
prismatic or cylindrical rods, the Gouy method is applied. A schematic representation of a
measuring device based on this method is shown in Fig. 9.1.1.
The sample is suspended using a long string and a small counterweight to prevent the
sample from being pulled to one of the magnet poles. One end of the rod-shaped sample is
located between the poles of a magnet where the field strength is comparatively high. By
contrast, the field strength at the other end of the sample is small. The axial force exerted
on the sample by the field is measured, for instance, by using an automatic balance.
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