题目如图1所示,光滑的水平面上有质量为M的长木板以初速度v0向右运动,此时将一质量为m(mM)的物块放在木板的右端,设m与M间动摩擦因数为μ,欲使m不从M上掉下,问M的长度至少为多少?分析:1·分析运动过程,m相对于地面将向右做匀加速直线运动,M相对于地面将向右做匀减速直线运动, The problem is shown in Fig. 1. On a smooth horizontal surface, a long plank with mass M moves to the right at the initial velocity v0. At this time, a mass of m (in mM) is placed on the right end of the plank, and the distance between m and M is set. The dynamic friction factor is μ. To make m not fall off from M, what is the length of the M? At least: How to analyze the motion: m analyzes the motion process. M will move to the right and perform acceleration linear motion to the right. M will move toward the ground. Right to make a uniform linear motion,