极值法是通过把某个物理量推向无穷大或无穷小后对问题作出分析和判断。在高中物理教学中,有时候用极值法分析问题可以让复杂的问题简单化,特别是做客观题时往往会取得事半功倍的效果。下面这道题是笔者的一点思考,不足之处敬请大家批评指正。题目:在“探究加速度与力、质量的关系”实验中,某小组同学实验时先正确平衡摩擦力,通过改变沙的质量 The extreme value method analyzes and judges the problem by pushing a certain physical quantity to infinity or infinity. In high school physics teaching, sometimes analyzing the problem by extremum method can make the complicated problem simple, especially when it is objective problem, it will often achieve a multiplier effect. The following question is the author’s point of thinking, inadequate, please criticism correct. Title: In the experiment of “exploring the relationship between acceleration and force and quality”, a group of students experimentally correctly balance the friction force and change the quality of sand