自2003年高考中最后一道大题以传送带传送物体为情境考查物体受力和能量转化以来,高考中多次出现传送带为背景的命题,很显然它已成为高考命题的一个热点.而这类问题的难点有两个,一是被传送物体的受力情况的分析;二是传送带系统做功与能量转化问题.下面笔者就结合实例对这两个问题做一个粗浅分析.一、摩擦力突变问题 Since 2003, the last college entrance examination in a big problem with the conveyor belt to test objects for the context of stress and energy conversion since the college entrance examination appeared many times as the background of the conveyor belt, it is clear that it has become a hot topic college entrance examination proposition. There are two difficulties, one is the analysis of the force transmitted by the object; the other is the conveyor system to do work and energy conversion problems. The author will combine examples to do a superficial analysis of these two issues. First, the friction mutation problem