在电磁感应现象中,回路中感应电动势的瞬时值与平均值,通过导体横截面的电荷量的计算,感应电流流过电阻产生电热的计算,一直是中学物理教学的难点。本文结合自己的实际教学经验,对这几个问题进行了研究,在实际教学中如果能引导学生进行这样的讨论,对学生掌握本内容是有较大的帮助的。 In the phenomenon of electromagnetic induction, the instantaneous value and average of the induced electromotive force in the loop, through the calculation of the amount of electric charge in the cross-section of the conductor, the calculation of the electric heat generated by the induced current flowing through the resistance has been a difficult point in the physics teaching of middle school. Based on my own practical teaching experience, this article has carried on the research to these several questions, if can guide the student to carry on such discussion in the actual teaching, has the help to the student master this content.