镜像对称的载流导线磁场方向的分析  

ANALYSIS OF MAGNETIC FIELD DIRECTION OF CURRENT-CARRYING WIRES WITH MIRROR SYMMETRY

作　　者：梁雄[1] 赖国忠[1] 

机构地区：[1]龙岩学院,福建龙岩364012

出　　处：《物理与工程》2016年第5期82-84,共3页Physics and Engineering

基　　金：福建省自然科学基金资助项目(2014J01016)

摘　　要：电磁场的对称性分析在大学物理教学中有着极其重要的地位,但是现有的大学物理教材很少给出如何利用稳恒磁场的对称性来分析磁感强度的方向.文章针对此问题应用毕奥-萨伐尔定律并结合矢量的分解更加便捷地分析了一对镜像对称的载流导线在中间面上任意点处的磁场方向:其方向必定垂直于该面.应用这一结论可以很容易判断出像密绕螺线管、直螺线管和圆柱形导线等这一类电流分布具有镜像对称的载流导线在其中间面上的磁感强度的方向.The symmetry analysis of electromagnetic field plays an important role in the college physics teaching.But the current textbooks of university physics lack the analysis process of magnetic field direction,during solving a high symmetric static magnetic field by Ampere circulation theorem.Combining with vector decomposition,this paper presents the analysis of the magnetic field direction of current-carrying wires with mirror symmetry by the Biot-Savart law,and draws a conclusion that their magnetic field on a middle plane must be perpendicular to the plane.As applications of our conclusion,it is easy to judge the direction of magnetic field on the middle plane in this kind of mirror symmetry systems,such as the tightly wound solenoid,the straight solenoid,the cylindrical wire,and so on.

关 键 词：毕奥-萨伐尔定律 矢量分解 镜像对称 磁场方向 

分 类 号：O441-4[理学—电磁学] G642[理学—物理]