四只完全相同的滑轮和两根相同的绳子组成右图所示的甲、乙两个滑轮组，分别用来匀速提升同一重物时所用的拉力为F甲和F乙，机械效率为η甲和η乙，如不计摩擦，则F甲_1F乙，η甲_2η乙（选填：“＞”、“＜”_刷题宝

题干

四只完全相同的滑轮和两根相同的绳子组成右图所示的甲、乙两个滑轮组，分别用来匀速提升同一重物时所用的拉力为F_甲和F_乙，机械效率为η_甲和η_乙，如不计摩擦，则F_甲____ F_乙，η_甲____ η_乙（选填：“＞”、“＜”或“＝”）

上一题下一题 0.0难度选择题更新时间:2017-11-29 09:31:53

答案(点此获取答案解析）

＞,＝

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