题目内容

“力”的概念的敢学
我在讲课时，问同学们知道“力”吗？大家都说知道。但我问到“力到底是什么”时候？同学们却答不出来。我就接着说：“谁能说出力的表现？”于是，他们活跃起来了。有的说“人提水”；有的说“起重机吊钢管”；还有的说“磁铁吸引铁钉”。我和同学们一起讨论，同时辅以适当的演示实验，并板书如下：
接着布置归纳分析：从上述几个力的表现的例子可以看出，力是离不开物体的，如人、起重机、磁铁都是物体，水、钢管、铁钉也是物体。我进而又指出：“提、吊、吸”在物理学中都称为作用。由此得出力的初步概念：“力是物体对物体的作用。”

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