[题目]长度分别为l1和l2的两根不可伸长的细绳,悬挂着质量分别为m1和m2的两个小球,处于静止状态,如图1所示.中间小球m1突然受到一水平方向的冲击力、瞬间获得水平向右的速度v,求此时两绳图1图2图3中的拉力.[错解]小球m1以速度v、半径l1做圆周运动,用质点系牛顿第二定律,系统受 [Title] Two inextensible strings of length l1 and l2, respectively, hung two balls of mass m1 and m2, respectively, at rest, as shown in Fig. 1. The middle ball m1 suddenly receives a The impact force in the horizontal direction instantaneously obtains the horizontal speed v to the right. At this time, the tension in the two ropes shown in Fig. 1, Fig. 2, Fig. 3 is calculated. [Mission] The ball m1 makes a circular motion with velocity v and radius l1. Newton’s second law, system