电磁学中的物理模型

建立物理模型是研究物理学的重要方法之一。物理模型是真实客体高度抽象的理想化形态,它既简化了客体,又形象了客体,它是真实客体的近似描述。本文首先从几则具体实例出发,分析使用物理模型时经常出现的一些似是而非的问题,从而阐明物理模型与客体的关系。使用物理模型时必须始终不忘物理模型是从怎样的客体抽象而来的。因此,如果空谈物理模型而忽视它的使用条件和使用范围,往往导致荒唐的结论。文中举例只涉及电磁学的内容,对于物理学中其它方面的内容,这一思想是共通的。

The Physical Models in Electromagnetics

Building physical models is one of the most important methods for physics it-search. Physical models are the highly abstract idealized formation of real objects. As the approximate expression of objects, they are simpler, but mere imaginal than objects. Through several examples, we analyse some specious problems that we may meet frequently, thereby expound the relation between models and objects. When using a model, we should always note how it is abstracted from object. It may lead to ridiculous results to neglet the comlitions and the limits for using physical models. Examples presented here only involve electromagnetics, but the ideal about the models are common in the whole physics.