本文对普遍存在于高中物理奥赛教程及大学普通物理辅导资料中的一道力学题进行了深入研究.题目.如图1所示,一细绳悬挂一质量为M的光滑圆环,在圆环上套着质量均为m的2个小球,今同时将2个小球从最高点A释放,并沿相反方向自由滑下.试求(1)小球与圆环的质量比mM至少为多大时圆环才有上升 This article has carried on the thorough research to a mechanics problem which is ubiquitous in the high school physics Orsay tutorial and the university general physics guidance material topic.As shown in Fig. 1, a thin rope suspends a smooth ring of mass M, Two sets of pellets of mass m are now released and at the same time, two pellets are released from the highest point A and slide freely in the opposite direction. Try (1) How much is the mass ratio of pellet to ring? When the ring rose