EXPERIMENTAL RESEARCH OF THE ELECTRIC FIELD POTENTIAL OF A ROTATING MAGNETIZED SPHERE

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We performed an experiment for the veriflcation of existing theoretical formulas for the electric fleld potential of a rotating magnetized sphere. Measurements of the electric fleld potential difierences across cylindrical capacitors were carried out. Experimental results are essentially in accord with the potential obtained using the special relativity transformations and contradict formula for the quadrupole fleld potential. Below, in a brief review, the theoretical formulas for the electric potential and electric fleld intensity of a rotating magnetized sphere are given, and some experimental results are discussed. It is known that a homogeneously magnetized sphere rotating around the axis parallel to the magnetic moment of the sphere is the source of the potential electric fleld (1). There exist difierent calculation methods for the electric fleld potential ' of the rotating magnetized sphere. The flrst, the simplest one, supposes that the Lorentz force induces a displacement of free or bond electric charges rotating with a magnet. The Lorentz force is produced by the rotating magnetized body's self-magnetic fleld (2). This method gives the correct value of the unipolar induction e.m.f. acting between the pole and the equator of the sphere and the quadrupole electric fleld. However, in the experiment of Wilson and Wilson (3), the Einstein's formula has been conflrmed. Based on this result we can conclude that the charge polarization of the rotating magnetic insulator is observed only in the external magnetic fleld of a coil that is at rest in the lab frame, and the self-magnetic fleld of a rotating magnetic dielectric does not produce any polarization. In the experiment in (4), we attempted to detect free charges displacement in an aluminum conductor which was mounted on a magnet rotating together with the conductor. The experiment did not detect any displacement of the free electric charges in the conductor under the Lorentz force action. The second method is based on several elements of the special relativity followed by the boundary- value electrostatic problem solving. In this method, the material Minkowski equations (1), the magnetic fleld transformation (2,6) inside the magnetic sphere and the magnetic moment transformation (5,6) are used. In this case, it is implicitly assumed that the special relativity transformations are applicable in the rotating frame of reference. Solutions obtained by this method also give the quadrupole electric fleld potential of the rotating magnetized sphere. In particular, the expression for the scalar potential of the sphere | conductor ( = 1, | permittivity of the sphere), which was obtained using the material Minkowski equations, is (1)