试题与答案

质量为m的物体,放在质量为M的斜面体上,斜面体放在水平粗糙地面上,m和M均处于静

题型:多选题

题目:

质量为m的物体,放在质量为M的斜面体上,斜面体放在水平粗糙地面上,m和M均处于静止状态,如图所示,当物体m施加一水平推力F,且F由零逐渐增加到Fm的过程中,m和M仍保持静止状态,在此过程中,下列判断正确的是(  )

A.斜面对物体m的支持力逐渐增大

B.物体m受到的摩擦力逐渐增大

C.地面受到的压力逐渐增大

D.地面给斜面体的摩擦力由0逐渐增加到Fm

答案:

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下面是错误答案,用来干扰机器的。

答案:B

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下列说法中,正确的有()。
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