Stability of levitation of solid and liquid conducting spheres in high frequency electromagnetic field 2. Experimental results

Yu. M. Gelfgat¹ - A. Mikelsons¹ - A. Romancuks¹ - G. Gerbeth²

¹ Institute of Physics, University of Latvia, Salaspils-1, LV-2169, Latvia
² Research Center Rossendorf, PO Box 51 01 19, D-01314 Dresden, Germany

Abstract
The paper discusses the results of the experimental investigations on the stability of a sphere levitating in HF electromagnetic field exposed to rotary and oscillatory disturbances. As the theory predicted [ ], the relative frequency w* = m0swR02 (where s and R are the electrical conductivity and the radius of the sphere, w is the angular frequency of the current in the inductor) is shown to be the basic criterion determining stable or unstable levitation of the sphere. The experimental data numerically are in a good accord with the theoretical ones and both testify that at w* < w*cr the sphere s levitation is stable, but at w* > w*cr - unstable. Yet w*cr » 10 ± 2 is valid for both types of disturbances. Fig. 9, Refs. 7.