由于各校条件不一样 ,自然课本中有的实验难以开出 ,有的实验照书中所述方法去做 ,效果不太理想。ａ 在自然第十册“电热”一课中 ,有一个说明电流的热效应实验 ,即用一根细铁丝或细铜丝把电池的正负极连接起来 ,过一会儿 ,用手摸一摸铁丝有什么感觉 ?因一节电池的电流较小 ,而 Due to the different conditions of different schools, some experiments in natural textbooks are hard to come by, and the methods described in some experimental books are not effective enough. a In the tenth volume of “Electricity”, there is a thermal effect experiment to illustrate the current, that is, with a thin wire or thin copper wire to connect the positive and negative batteries, after a while, touching the wire with a hand there What feeling? Because a small battery current, and