如图所示，用一根绳子绕过定滑轮，一端拴在钩码上，手执另一端，分别用力F1、F2、F3匀速拉起钩码．忽略绳子与滑轮的摩擦，下列说法中正确的是_刷题宝

题干

如图所示，用一根绳子绕过定滑轮，一端拴在钩码上，手执另一端，分别用力F₁、F₂、F₃匀速拉起钩码．忽略绳子与滑轮的摩擦，下列说法中正确的是（　　）

A：F₁较大

B：F₃较大

C：F₁、F₂、F₃的大小不能确定

D：将钩码提升相同的高度，力F₁、F₂、F₃所做的功相等

上一题下一题 0.0难度选择题更新时间:2016-02-16 10:51:27

答案(点此获取答案解析）

D

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