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> 氢气球用绳子系着一个重物，共同以10m/s的速度匀速竖直上升，当到达某一个高度时，绳子突然断开，这个重物将 A.以原来的速度一直上升 B.继续上升一段，然后下落 C.动能增加 D.重力势能保持不变

问题：

发布时间：2024-09-10

氢气球用绳子系着一个重物，共同以10m/s的速度匀速竖直上升，当到达某一个高度时，绳子突然断开，这个重物将

A.以原来的速度一直上升
B.继续上升一段，然后下落
C.动能增加
D.重力势能保持不变

参考答案：

提问用户：de***knB

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