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近年中考中,杠杆知识点考查形式主要有选择题、填空题、作图题、计算题和实验探究题等多种题型,考查的内容包括杠杆的五要素(支点、动力、动力臂、阻力、阻力臂)、判断杠杆是省力还是费力杠杆、杠杆平衡条件实验及应用等.一、杠杆的辨析判断杠杆类型的中考题主要有两种,一是判断是否属于杠杆,主要根据杠杆的定义来判断;二是杠杆类型的判断,杠杆主要包括以下三种:(1)省力杠杆,动力臂大于阻力臂;(2)费力
In the middle school entrance examination in recent years, there are a variety of questions such as multiple choice questions, fill-in-blank questions, drawing questions, calculation questions and experimental inquiry questions. The content of the examination includes five elements of leverage (fulcrum, motive force, , Resistance arm), to determine whether the lever is labor-saving or laborious lever, lever balance conditions experiment and application, etc. First, the lever discrimination Judge the type of lever in the exam there are two main, one is to determine whether the lever, mainly based on the definition of leverage Judgments; second, judgments on the type of leverage, the lever includes the following three: (1) labor-saving lever, power arm is greater than the resistance arm; (2) effort