摘要
本文避开张量概念，由洛仑兹力公式的协变性，来讨论电磁场的变换关系．进而说明电磁场的相对性，并通过一具体事例讨论不同参考系中电磁场的来源．
In accordance with covariance of Lorentz force formula. this article avoids theconcept of tensor to discuss Variable relation of electromagnetic field. and then illustrates relativity of electromagnetic field. Through a concrete example, the article also disscusses how electromagnetic field comes into being in different reference system.
关键词
惯性系
力
变换关系
相对性
洛仑兹长度收缩
电场
磁场
electromagnectic field, intertia system, variotion in force,Lorentz contraction
