竖直平面内的圆周运动,是典型的变速圆周运动问题,中学物理中只研究物体通过最高点和最低点的情况,并且经常出现临界状态,下面对这类临界状态进行分类分析.1如.图外1轨、所绳示的,约没束有情物况体支持的小球,在竖直平面内做圆周运动过最高点的情况.(1)临界条件小球到达最高点 The circular motion in vertical plane is a typical variable circular motion problem. In middle school physics, only the object passing through the highest point and the lowest point is studied, and the critical state is often seen. The following is a classification analysis of such critical states.1 For example, In the figure 1, there is about no ball in the vertical plane, and the maximum point of circular motion in the vertical plane is reached. (1) The critical condition The ball reaches the highest point