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    精英家教网 > 初中物理 > 题目详情
    按照图的要求画出滑轮组的绕绳方法(不计滑轮重、绳重及摩擦)

    试题分析：动滑轮被几根绳子承担，拉力就是物体和动滑轮总重的几分之一（1）F=，由4段绳子承担滑轮的重；（2）F=，由5段绳子承担滑轮的重．

    点评：滑轮组设计原则可归纳为：奇动偶定；一动配一定，偶数减一定，变向加一定．
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