关于“等量同种电荷连线中垂线上电场强度大小变化的问题” ,在以往的教学中 ,交待给学生的只是一个填鸭式的定性的结论 :“从等量同种电荷连线的中点沿着中垂线向两侧伸展开去 ,电场强度先增大后减小 .”在研究性学习的教学理念的引导下 ,我考虑还需对学生做进一步的设问 :“ Regarding the problem of the change in the magnitude of the electric field on a vertical line in the same charge line of the same kind, in the previous teaching, the only explanation given to the student was the qualitative conclusion of a spoon-feeding type: “Connected from the same charge of the same kind. The midpoint extends along both sides of the vertical line, and the electric field intensity increases first and then decreases.” Under the guidance of the teaching philosophy of research learning, I considered that further questions need to be given to students: “