Measuring Magnetization by Force:

In case of the samples in liquid or powder forms, they have to be filled in rod-shaped container as shown in Figure 28.03 and suspend it vertically so that one end is between the pole-pieces of the magnet. In such scenario, the force on the element is

which can be rewritten as

Figure 28.03: Schematic drawing of Gouy's method for measuring magnetization by force.

Integrating along the length of the rod gives

where B₁ and B₂ are the magnetic field values at each end of the rod. Considering one end is far from the center, then B₂ →0. Therefore,

This technique is known as Gouy's method.