ABSTRACT
A magnetic field in the region where the real current is placed can be established as a superposition of the field from the real current and all its images, placed in the same uniform medium, in which the real current was located. The resultant magnetic field intensity on the cover surface can be calculated from the law of flow, with application of the superposition principle. This chapter presents a classical method of determining magnetic field in a circular slot, in a trapezoidal slot, and in a rectangular slot. The theory of an electrostatic field limited by iron boundaries is often applied to the solution of constructional systems with an alternating current excitation. The saturation of the iron is usually of less hindrance. In a general case, the mirror image method can be applied for combination of fields produced by steel cores and coils with current.
