如图所示，动滑轮重0.5N，物体重3.5N，当OA=2OB时，为使轻质杠杆保持水平平衡、在A端所加的力应为（不计摩擦）_刷题宝

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如图所示，动滑轮重0.5N，物体重3.5N，当OA=2OB时，为使轻质杠杆保持水平平衡、在A端所加的力应为（不计摩擦）（）

A：0.5 N 　

B：1N

C：2N　

D：4N

上一题下一题 0.0难度选择题更新时间:2018-01-21 10:03:17

答案(点此获取答案解析）

B

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