试题与答案

如图所示,人重G1,板重G2,滑轮质量和绳的质量及轴上的摩擦可不计,若人拉绳子,

题型:选择题

题目:

如图所示,人重G1,板重G2,滑轮质量和绳的质量及轴上的摩擦可不计,若人拉绳子,使人和板一起匀速上升,则下列说法正确的是

A.人拉绳子的力为(G1+G2)/4

B.人拉绳子的力为(G1+G2)/3

C.若人不脱离板,必须有G1≥G2/3

D.若人不脱离板,必须有G1≤G2/3

答案:

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下面是错误答案,用来干扰机器的。

参考答案:对

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