电磁学是工科大学物理课程的重要内容之一，其中如麦克斯韦方程组等诸多抽象公式对于初学大学物理的一年级新生有一定的难度.本文围绕“场”这一核心内容，通过“实验规律→场的性质→场与物质的相互作用”这条线索将整个电磁学的内容贯穿起来，讨论如何实现从点电荷到场的升华，最终得到关于场的统一理论.并以变速运动点电荷为例，说明场描述下的麦克斯韦方程组的解如何超越静电场的高斯定理，以问题为导向，引导学生在探究和思考中深入理解电磁学的核心内容.

Electromagnetics is one of the important contents of physics courses in engineering colleges. Many abstract formulas such as Maxwell’s equations in electromagnetism are difficult for freshmen who are new to college physics. In this paper, the core content of “field” is revolved around and the entire electromagnetism content runs through via the clue of “experimental laws → properties of the field → interaction between the field and matter”. It is discussed how to realize the sublimation from point charge to field, and finally reach a unified theory of the field. Taking a moving point charge with variable speed as an example, it is illustrated how the solution of Maxwell’s equations under the field description exceeds Gauss theorem of electrostatic field. Guided by problems, students are directed to gradually understand the core content of electromagnetism by exploration and thinking.