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在图中,杠杆在力F1和F2的作用下处于静止状态,l2是力F2的力臂。请在图中画出F1的力臂l1和力F2
答案见解析。

试题分析:动力臂是支点到动力作用线的距离。阻力臂是支点到阻力作用线的距离。根据要求准确地画出力臂。
点评:了解动力臂和阻力臂的画法是作图的前提。
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