问题 多项选择题

如图3所示,倾斜放置的木板上固定有一光滑滑轮,质量为M、m的Q、P两物体用轻质的细绳连接后绕过滑轮,物体Q静止在木板上。已知M=2m,开始木板的倾角为θ,现增加θ角,如果系统仍然能够保持静止状态,则θ角增加过程中下列说法错误的是()

A.细绳的拉力一定增大

B.物体Q对斜面的压力一定增大

C.物体P受到的静摩擦力大小可能不变

D.物体Q受到的合力始终不变

答案

参考答案:A, B

判断题
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