现行各版本的高中物理教材在引入“加速度”的概念时,都是从速度大小的变化去引入的,这种引入方法很容易使学生将“速度大小的变化”与“速度变化的大小”混为一谈,进而使“速度变化的方向”成为该节教学一大难点.要突破这一难点,单纯在直线运动中研究是有困难的,应该按照从一般到特殊的顺序来进行. Current versions of high school physics textbooks are all introduced from a change in speed when introducing the notion of “acceleration.” This introduction method makes it easy for students to change the “speed” and “speed” The size of the change “to confuse, and thus make” the direction of the speed of change "become a major difficulty in the section teaching.To break through this difficulty, simply in the study of linear motion is difficult, according to the general to the special order To carry out.