首页 / 如图所示，质量均为M的物体A和B静止在光滑水平地面上并紧靠在一起

如图所示，质量均为M的物体A和B静止在光滑水平地面上并紧靠在一起

如图所示，质量均为M的物体A和B静止在光滑水平地面上并紧靠在一起（不粘连），A的ab部分是四分之一光滑圆弧，bc部分是粗糙的水平面。现让质量为m的小物块P（可视为质点）自a点静止释放，最终刚好能到达c点而不从A上滑下，则下列说法中正确的是                                                                                 （    ）

       A．小物块P到b点时，A的速度最大

       B．小物块P到c点时，A的速度最大

       C．小物块P到b点时，P的速度最大

       D．小物块P到c点时，A的速率大于B的速率

答案

AC

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