磁铁的性质片断实录（出示用纸包着的条形磁铁和蹄形磁铁各一块）师：两块磁铁外面都用纸包着，有什么办法知道它们的两端分别是什么极？请讲出你的理由是什么？同学们议论开了。生：让它们的一端相互接近，根据“同极相斥、异极相吸”，可以测出它们的两端分别是哪一极。... Magnet properties of the pieces recorded (showing the paper wrapped bar magnets and hoof magnets each) Teacher: Two magnets are wrapped in paper, what are the two ways to know what are the poles? Please tell me what is your reason? Students talked about it. Students: Let their ends close to each other, according to “the same repulsion, heterosexual absorption”, can be measured at both ends of their respective poles. ...