在中学物理教学中,自由落体的演示实验是个不易做得成功的实验,按一般书上介绍看频闪照片的方法不够直观,学生印象不深刻;如照原高中物理第一册(1955年第一版)中介绍的落棍实验装置来演示,却存在着这样的几个问题:(1)落棍开始下落跟笔在棍上划下的第一划记号时不能同步。(2)落棍在下落过程中容易发生转动和晃动,使得笔尖有时不能在落棍上划下记号。(3)笔尖在落棍上所划下的记号是 In the middle school physics teaching, the free-fall demonstration experiment is an experiment that is not easy to do successfully. The method of reading the strobe photos according to the general book is not intuitive, and the students’ impression is not profound. For example, according to the original high school physics book (No. 1955) There are several problems with the demonstration of the fall stick device introduced in the first edition: (1) The fall of the stick can not be synchronized with the first stroke marking the pen on the stick. (2) The falling stick tends to rotate and shake during the falling process, so that the pen tip sometimes cannot mark the falling stick. (3) The mark marked by the pen tip on the stick is