在初中物理第二册.第十章中讲述了三个定则.即安培定则、左手定则和右手定则。对于后两个定则的应用学生普遍感到很困难.往往把定则用错。我在教学实践中认识到对这两个定则应用必须从能量转化的角度加深理解。 In the junior high school physics second volume. Chapter ten describes three rules, namely the Ampere’s rule, the left-hand rule and the right-hand rule. Students generally find it difficult to apply the latter two rules. They often use the rules wrongly. In my teaching practice, I realized that the application of these two rules must be deepened from the perspective of energy transformation.