半径为r和R（r＜R）的光滑半圆形槽，其圆心均在同一水平面上，如图所示，质量相等的两物体分别自半圆形槽左边缘的最高点无初速度地释放，在下滑过程中两物体_刷题宝

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半径为r和R（r＜R）的光滑半圆形槽，其圆心均在同一水平面上，如图所示，质量相等的两物体分别自半圆形槽左边缘的最高点无初速度地释放，在下滑过程中两物体（　　）

A：机械能均逐渐减小

B：经最低点时对轨道的压力大小相等

C：两球在最低点加速度大小不等

D：机械能总是相等的

上一题下一题 0.0难度选择题更新时间:2019-10-28 08:16:05

答案(点此获取答案解析）

B,D

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