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在放学路上,我经常看见一群小鸟站在高压电线上叽叽喳喳。它们时而飞起,时而停落,好不自在。忽然,一个问题在我脑中闪现:科学老师曾告诉我们,人如果碰到带电的电线会触电,可小鸟为什么能站在高压电线上?难道高压电线没有电?一听旁边碾米厂里机器发出的轰鸣声,刚才的猜想马上被我否定了。在好奇心的驱使下,我一回到家就找来《十万个为什么》,决定查个究竟。书中的说理比较透彻,让我逐渐“拨开云雾见青天”。我们都知道,电源分为正、负两极。在正、负两极之间连接上导体,电流就会从导体流
On the way to school, I often see a group of small birds twittering on high-voltage wires. They sometimes fly, sometimes stop, very uncomfortable. Suddenly, a problem flashed in my head: the science teacher once told us that if a person touches a live wire, he will get an electric shock. Why can a small bird stand on a high-voltage wire? Does the high-voltage wire have no electricity? The roar of the machine, just guess I was denied immediately. Driven by curiosity, when I got home, I got “one hundred thousand why” and decided to check it out. The book in the more thorough argument, let me gradually “Pok cloud see the sky ”. We all know that power is divided into positive and negative poles. Connect the conductor between the positive and negative poles, and the current will flow from the conductor