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> 如图所示，两个完全相同的光滑球的质量为m，放在竖直挡板和倾角为α的固定斜面间．若缓慢转动挡板至斜面垂直，则在此过程中（　　） A．A，B两球间的弹力不变 B．B球对挡板的压力逐渐减小 C．B球对斜面的压力逐渐增大 D．A球对斜面的压力逐渐增大

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发布时间：2024-09-13

如图所示，两个完全相同的光滑球的质量为m，放在竖直挡板和倾角为α的固定斜面间．若缓慢转动挡板至斜面垂直，则在此过程中（　　）

A．A，B两球间的弹力不变

B．B球对挡板的压力逐渐减小

C．B球对斜面的压力逐渐增大

D．A球对斜面的压力逐渐增大

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