全日制高中物理课本下册,在讨论电感对交流电的阻碍作用时,采用两个独立的电路(课本166页图5—9和图5—10)来定性地演示说明。但原来电路存在着电源电压高和不便直观比较灯泡亮度等缺点,且制作成本高,操作不便。针对上述问题,笔者改装了原有电路,并制成了示教板。经多次使用,效果良好。现把有关问题作简单介绍如下。 The full-time high school physics textbook, in the next volume, discusses the inductive effect of AC on the use of two separate circuits (text 166, Figure 5-9 and Figure 5-10) to illustrate the qualitative description. However, the original circuit has disadvantages such as high power supply voltage and inconveniently comparing the brightness of the lamp, and the manufacturing cost is high and the operation is inconvenient. In response to the above problems, the author modified the original circuit and made a teaching board. After many uses, the effect is good. The relevant issues are briefly described below.