情景·案例在初四“惯性现象”的复习课中,为了加强学生对惯性现象的理解,笔者设计了一些与初中物理课本及参考书不同的实验。由于学生已经建立了“惯性”的初步概念,复习只是为了在原有的基础上加深对惯性的理解,学会分析问题、注重学以致用。其中有一个有关惯性的题目是:在铁架台上用棉线吊着一个质量较大的钩码,在钩码的下面系着一根与钩码上面相同的另一根棉线,现在用一个很大的向下的拉力迅速去拉钩码下面的那根棉线。请问:钩码上下两段相同的棉线,哪 Scenario · Case In order to strengthen students’ understanding of inertial phenomena in the reviewing course of the first four “inertial phenomena”, the author designed some experiments different from those of junior high school physics textbooks and reference books. Because students have established the initial concept of “inertia ”, the review is only to deepen the understanding of inertia on the basis of the original, learn to analyze the problem, pay attention to apply what they learn. One of the questions about inertia is that of hanging a large mass of hook code on the iron platform with a thread of cotton and attaching a different thread under the hook code to the same hook code as above and now using a large The pull down quickly to pull the hook code below that cotton. I ask: hook code up and down the same two lines of cotton, which