考点指要第25题考生平均得分4.6分,相对于总分20分来说只是个安慰性的分数,主要失分原因如下:1.答题时间不足,浅尝辄止,只得到步骤分。2.运动过程分析不清,受力分析不到位。本题属于两个物体的受力,相对运动的综合问题,有两个摩擦力,并且性质、大小均发生变化,考生需要边分析边计算,力和运动交替进行,难度很大。它 Test points means to 25 points average score of candidates 4.6 points, relative to the total score of 20 points is only a soothing score, the main reasons for the loss points are as follows: 1. The answer time is short, try it out, only get the points. 2 sports process analysis is not clear, force analysis is not in place. This problem belongs to the force of two objects, the relative movement of the integrated problem, there are two friction, and the nature, size have changed, the candidates need to analyze while computing, the force and the movement alternately, very difficult. it