文档介绍:Field and Wave ic 电磁场与电磁波 2014. 4. 2 2 1. Introduction 2. Fundamental Postulates of ostatics in free space F qE qu B ? ??? ? ?? Lorentz ’s force equation 0 B J ????? ? 0B ???? Differential form 0 S B ds ? ????? 0 C B dl I ?? ????? Integral form Postulates of ostatics in Free Space Review 3 3. Vector ic Potential 4. The Biot-Savart Law and Applications 0 B B A ???????? ?= 20 A J ?? ????;;; 0 20 20 2 zzyyxxJAJAJA????????????''0 (Wb/m) 4 VJ A dv R ??????' ' ' ' ' 0 0 2 3 ? (T) 4 4 R C C C I I aR B d l d l dB R R ? ?? ?? ????? ???? ?? ?? ?? 4 Main topic 静磁场 5 Example 6-6 求导线圈轴线上的磁通密度' ' ?' dl a bd ????'??' z r R op op za ba ? ????????????' ' ' 2 ?????' ' ' ' z r r z dl R bd a za ba a bzd a b d ?? ??? ? ?????????? 2 2 0 0 3/ 2 3/ 2 2 2 2 2 '?? (T) 42 z z c I Ib b d B a a b z b z ? ???? ?? ????''03 (T) 4 CIR B d l R ??? ?????? x zy Ib P'P oa’ ra’?a za za ’’ ra ’’?- a’ r 6 EXAMPLE 6-7 Find the ic flux density at a distant point of a small circular loop of radius b that carries current I ( a ic dipole ). Spherical coordinates R b ?''014 CI d l AR ???????( , , / 2) P R ?? x zy Ib'P o RR 1?’?dl’?'1?? dlR ???7 ' ' '