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向心力与向心加速度

> 如图，光滑水平圆盘中心O有一小孔，用细线穿过小孔，两端各系A，B两小球，已知B球的质量为2Kg，并做匀速圆周运动，其半径为20cm，线速度为5m/s，则A的重力为 [ ] A．250N B．2.5N C．125N D．1.25N

问题：

发布时间：2024-09-13

如图，光滑水平圆盘中心O有一小孔，用细线穿过小孔，两端各系A，B两小球，已知B球的质量为2Kg，并做匀速圆周运动，其半径为20cm，线速度为5m/s，则A的重力为

[ ]
A．250N
B．2.5N
C．125N
D．1.25N

参考答案：

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