Fundamentals of Engineering Electromagnetics(PNIE)
저자 / David Cheng 저
가격₩-
출간일2013.07.29
ISBN 101292026588
ISBN 139781292026589
페이지504p
판형193(W) X 241(H) X 24(T) (mm)
차례
1. The Electromagnetic Model.
Overview. The electromagnetic model. SI units and universal constants. Summary.
2. Vector Analysis.
Overview. Vector addition and subtraction. Vector multiplication. Orthogonal coordinate systems. Gradient of a s
책소개
From the Inside Flap
This book is designed for use as an undergraduate text on engineering electromagnetics. Electromagnetics is one of the most fundamental subjects in an electrical engineering curriculum. Knowledge of the laws governing electric and magnetic fields is essential to the understanding of the principle of operation of electric and magnetic instruments and machines, and mastery of the basic theory of electromagnetic waves is indispensable to explaining action-at-a-distance electromagnetic phenomena and systems.
Because most electromagnetic variables are functions of three-dimensional space coordinates as well as of time, the subject matter is inherently more involved than electric circuit theory, and an adequate coverage normally requires a sequence of two semester-courses, or three courses in a quarter system. However, some electrical engineering curricula do not schedule that much time for electromagnetics. The purpose of this book is to meet the demand for a textbook that not only presents the fundamentals of electromagnetism in a concise and logical manner, but also includes important engineering application topics such as electric motors, transmission lines, waveguides, antennas, antenna arrays, and radar systems.
I feel that one of the basic difficulties that students have in learning electromagenetics is their failure to grasp the concept of an electromagnetic model. The traditional inductive approach of starting with experimental laws and gradually synthesizing them into Maxwell's equations tends to be fragmented and incohesive; and the introduction of gradient, divergence e, and curl operations appears to be ad hoc and arbitrary. On the other hand, the extreme of starting with the entire set of Maxwell's equations, which are of considerable complexity, as fundamental postulates is likely to cause consternation and resistance in students at the outset. The question of the necessity and sufficiency of these general equations is not addressed, and the concept of the electromagnetic model is left vague.
This book builds the electromagnetic model using an axiomatic approach in steps--first for static electric fields, then for static magnetic fields, and finally for time-varying fields leading to Maxwell's equations. The mathematical basis for each step is Helmholtz's theorem, which states that a vector field is determined to within an additive constant if both its divergence and its curl are specified everywhere. A physical justification of this theorem may be based on the fact that the divergence of a vector field is a measure of the strength of its flow source and the curl of the field is a measure of strength of its vortex source. When the strengths of both the flow source and the vortex source are specified, the vector field is determined.
For the development of the electrostatic model in free space, it is only necessary to define a single vector (namely, the electric field intensity E) by specifying its divergence and its curl as postulates. All other relations...(하략)
