贵刊2005年第4期刊登了陈卫东、李俊二位老师“顺理不一定成章——向心加速度是描述速度方向变化的物理量吗?”的文章(以下称作“顺”文).笔者阅读后发现.“顺”文中的有些说法欠妥,有些观点甚至是错误的.由于“顺”文讨论的是中学物理力学中的基本概念,故认为很有必要对这些问题给予甄别与纠正.一、“顺”文在开始写到:“…加速度是描述速度变化快慢的物理量,而向心加速度只改变速度的方向,不改变速度的大小.”这段话存在科学性的错误,其理由 In your issue of the 4th issue of the magazine published in the 4th issue of your magazine, Chen Weidong and Li Jun’s two teachers “isn’t necessarily a rule—is the centripetal acceleration the physical quantity to describe the direction of change in speed?” (hereafter referred to as “Shun”). Later, it was discovered that some of the arguments in the “Shun” text were not correct, and some of the opinions were even wrong. Since the “Shun” article discusses the basic concepts in the middle school physics and mechanics, it is considered necessary to identify and correct these problems. “Chun” wrote at the beginning: “...Acceleration is the physical quantity that describes the speed change, while the centripetal acceleration only changes the direction of the speed, and does not change the speed.” There is a scientific error in this passage, and its reason