电容器易错问题分析

An Analysis of the Mistake-prone Problems of Capacitors

分别从场和能量的角度、电位的角度分析了电容器间电压、能量的分配,讨论了平行板电容器间插入金属板,改变平行板电容器极板间的距离时场强、能量等问题,分析了易产生错误的原因,指出抓住电容器与电源是否连接,以及有无外力做功、电源做功发生,从而根据能量守恒,弄清能量的变化来分析解决问题比较方便。

This paper analyzes the distribution of voltage and energy in a capacitor from the perspective of field and energy and the perspective of electric potential.In addition,it discusses the field intensity and energy issues when inserting a metal plate into the parallel-plate capacitor and changing the distance between the plates of the capacitor.The reasons why people are likely to make mistakes with respect to this are analyzed.It shows that people should get the hang of whether the capacitor and the power supply are connected and whether external force and the power do work.And the problems can be solved conveniently on the basis of energy conservation and a clear understanding of the energy change.