论文部分内容阅读
在初中物理第二册“电磁铁”一节的教学中，教材上关于“制作、研究电磁铁”的学生实验是这样的：用图１这些器材制作电磁铁：先用细漆包线在大铁钉上顺着一个方向绕制两个匝数不同（４０匝和８０匝）的线圈，再用棉线缠绕固定，使漆包线不致松散，这就制成了两个简单的电磁铁
In the teaching of the “Electromagnetic” section of Physics Book 2 of Junior Middle School, the student’s experiment on “making and studying electromagnets” in the teaching materials is as follows: Use these devices as shown in Figure 1 to make electromagnets: first use fine enameled wire in big iron nails Two coils with different numbers of turns (40 turns and 80 turns) are wound in one direction, and then wound with a cotton thread so that the enameled wire is not loosened. This results in two simple electromagnets.