We have performed detailed measurements of two components,and, of the electric field vector in high-superconducting (HTS) ceramics,, as functions of the transport current along the z-axis and of the anglebetween a constant external magnetic field applied in the sample plane and the current direction. Note that we are aware of no other publications concerned withmeasurements. It was found thatdepends ononly slightly, varying by, andis of the order of 0.1. Two types ofdependence are possible in the low-field electrodynamics. In this domain the HTS ceramic is a Josephson medium, with the penetration of magnetic field into it governed by the parameterwhere a is the grain size,is the flux quantum andis the critical current density. If, then the effective penetration depth, and the conventional flux-line-cutting model, characterized by a parametrically large anisotropy ofand, is valid. If, then the effective medium theory is inapplicable, and the current - voltage characteristics (CVCs), related to the penetration of magnetic field quanta through single Josephson junctions, are determined by the nonlinear properties of these junctions, which are independent of the angle. It is this fact that leads to an isotropic CVC. Our results indicate that the second situation is realized.
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