在初中阶段运用回声原理测量距离一般有五种题型,很多同学对这几种题型容易混淆。所以本文主要是针对这几种题型进行解析,希望对同学们有所帮助和启示。一、回声原理题例1一个人面对高墙喊了一声,要想把自己的叫声和原声区别开,这个人至少离高墙多远?(常温下空气中声速为340m/s) In the junior high school stage using echogenic principle to measure distance generally five kinds of questions, many students easily confused these types of questions. Therefore, this article is mainly for these types of questions to analyze, I hope to help students and enlightenment. First, the echogenic principle Example 1 a person shouting at the face of the wall, in order to distinguish their voices and the original sound, this man at least from the wall far? (Room air temperature of 340m / s)