Simultaneous measurement of electrical and magnetic properties of a spherical sample

A method using a solenoid coil for simultaneously estimating the electric and magnetic properties of a spherical conductor was studied, These properties are estimated by finding the difference in the complex impedance of the coil with and without a sample to find out the measuring value that best coincides with the theoretical value. A formula applicable to a non-magnetic, a magnetic or a superconductive spherical sample was derived. The conductivities measured by this method and by DC four-probe method were compared using spherical samples of copper, aluminum and brass of different radius. The deviations between the two methods were no larger than 3%