刚刚接触电学的同学,大都对电十分感兴趣。从摩擦起电到两种电荷,从奥斯特实验到电磁感应,电把同学们带进了一个神奇的世界。然而,好多同学由于刚刚接触电学知识,所以常常感到电学既吸引人又迷惑人。那一个个电学公式虽然比数学公式简单,但因每一个字母都有它的物理意义,所以理解和记忆起来就觉得很困难。为此,我针对初中电学中最常见的几个物理量:电压U、电流强度I,电阻R和电功率P之间的关系,制作了一个小玩具——初中电学公式速查盘,如图1、2所示。同学们只要将1、2两盘分别沿外圆剪下,并将盘1中画斜线的部分挖掉,按照盘1在上、 Most of my classmates who have just come into contact with electricity are interested in electricity. From frictional charge to two charges, from the Auster experiment to electromagnetic induction, electricity brought the students into a magical world. However, many students often feel that electricity is both attractive and confusing because they have just come into contact with electrical knowledge. Although the electrical formulae are simpler than the mathematical formulae, because each letter has its physical meaning, it is difficult to understand and remember. For this purpose, I have developed a small toy for the most common physical quantities in junior middle school electricity: voltage U, current intensity I, resistance R, and electric power P. The junior high school electric formula cheat sheet is shown in Figure 1. 2 shows. As long as the students cut the 1st and 2nd discs along the outer circle, and dig out the sloping parts of the disc 1, follow the disc 1 above.