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向心力与向心加速度

> 一个质量为M的物体在水平转盘上，距离转轴的距离为r，当转盘的转速为n时，物体相对于转盘静止，如果转盘的转速增大时，物体仍然相对于转盘静止，则下列说法中正确的是 [ ] A．物体受到的弹力增大 B．物体受到的静摩擦力增大 C．物体受到的合外力不变 D．物体对转盘的压力减小

问题：

发布时间：2024-09-07

一个质量为M的物体在水平转盘上，距离转轴的距离为r，当转盘的转速为n时，物体相对于转盘静止，如果转盘的转速增大时，物体仍然相对于转盘静止，则下列说法中正确的是
[ ]
A．物体受到的弹力增大
B．物体受到的静摩擦力增大
C．物体受到的合外力不变
D．物体对转盘的压力减小

参考答案：

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