دانلود کتاب الکتریسیته و مغناطیس، فرمول‌بندی جدید با معرفی ابررسانایی

This textbook includes magnetic phenomena associated with superconductors in its description of electricity and magnetism, which successfully contribute to strengthening the E-B analogy. In the second edition, the equipotential surface and equivector potential surface were included, and the equivector potential surfaces were classified into two groups, i.e., one parallel to and the other not parallel to the magnetic flux lines. This contributed to widening the window of the E-B analogy. There are various phenomena that deserve attention, even in introductory studies of electricity and magnetism, and the author has published a book of exercises on electricity and magnetism to provide opportunities for students to systematically learn the physics. While collecting the exercises, the author found some new aspects of electromagnetic phenomena which seem to be important for education, and this finding has inspired the author to issue the third edition. For example, it is recommended to determine the inductance using the magnetic energy in the case where current flows over some area, since the magnetic flux cannot be calculated precisely. The reason for this method is clarified in this book. The use of the vector potential was strongly recommended from the viewpoint of the E-B analogy, and a new method is now shown to use it to directly determine the electromotive force. A new aspect can also be shown by adopting the gauge of the electromagnetic potential in exercises, which was only described in the earlier textbook. New exercises are introduced to enable the student to learn about the flow of energy into a capacitor during the process of charging or into a power transmission line while increasing a current with the Poynting vector. In particular, the comparison between the cases in which the power transmission line is made up of a usual conductor or a superconductor, which is one of highlights of this textbook, provides a good chance to learn about diverse electromagnetic phenomena. It is clarified that the formulae associated with the vector potential do not hold for the superconducting case. Nevertheless, the readers will finally learn the strong validity of Maxwell’s theory that can even allow such deviations. It is expected that the readers will be enabled to deeply understand electricity and magnetism with this new textbook and Exercises in Electricity and Magnetism by the same author.