静电学中,引入电荷后相互平衡问题,很多学生感到头痛,遇到这类问题学生抓不到规律性的东西,感到无从下手．其实,这类问题,关键是找出规律,学生只要抓住规律,问题就能得到简化,处理起来也很容易．一、两个点电荷固定,引入第三个点电荷,仅使第三个点电荷平衡的问题 In electrostatics, the problem of mutual balance after the introduction of charges has caused many students to feel headaches. When students encounter such problems, they cannot grasp the regularities and feel that they cannot start. In fact, the key to this kind of problem is to find out the rules. Students can grasp the rules and the problems can be simplified and dealt with easily. One or two point charges are fixed, the third point charge is introduced, and only the third point has the problem of charge balance