“信息的传递”一章与现代社会的联系非常密切,其中很多技术是比较尖端的高新科技,具有鲜明的时代性和科技性.由于这部分知识学习起来比较抽象,有些同学对相关的概念和公式缺乏正确的认识,所以解题时经常会犯一些错误.易错点一:电话机的工作原理 “The transmission of information ” chapter is very close with the modern society, many of which are more sophisticated high-tech, with a distinct era and science and technology.Because this part of the knowledge to learn more abstract, some students related to Concepts and formulas lack the correct understanding, so often make mistakes when solving problems. Error-prone point one: the working principle of the phone