Eddy currents, which are induced in a conductor by a non-steady external magnetic field, have been calculated and compared with experimental results. The analytical solution for spherical samples has been found to agree very well with the numerical results of the finite element package FEMM for large samples (the iron sphere). For small samples and at small distances from the symmetry axis rather large deviations have been found. The analytical solution is about twice as high as the numerical solution for the copper sphere. However, the numerical solution is still about twice as high as the experimentally found magnetic moment.
The agreement between numerical and experimental results is better for cylindrical samples.
There are a few remarkable aspects about the analytical solution for spherical samples:
* Only a, b, and D are functions of 
, the radius of the sphere. Since 
is proportional to a the radius 
influences only the scaling of 
and therefore of the eddy currents.
*
* The ''shape'' of the real and imaginary parts of 
is always given by the Bessel function 
. Only k, which is a function of the frequency, the magnetic permeability, and the conductivity, enters into the Bessel function.
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