判断反馈极性、类型的一种简明方法

A Simple Method for Judging Feedback polarity and Type

指出一般教材中反馈极性、类型的判断方法及其存在的困难 ;对一些文献中的简捷方法提出质疑 ;给出一种简捷明了。

This article points out the existing difficulties in some methods for judging feedback polarity and type in some physics textbooks and questions some.It also gives a kind of simple,clear and widely applicable method.