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杠杆的动态平衡分析

> 如图所示，杠杆OA的B点挂着重物G，A端用细绳挂在圆弧EF上，此时OA恰成水平，且A点与圆弧形架EF的圆心重合．当绳AM的M端从E点缓慢滑到F点的过程中，绳对A点拉力的大小将（　　） A．逐渐变大 B．逐渐变小 C．先变大再变小 D．先变小再变大

问题：

发布时间：2024-09-13

如图所示，杠杆OA的B点挂着重物G，A端用细绳挂在圆弧EF上，此时OA恰成水平，且A点与圆弧形架EF的圆心重合．当绳AM的M端从E点缓慢滑到F点的过程中，绳对A点拉力的大小将（　　）

A．逐渐变大 B．逐渐变小

C．先变大再变小 D．先变小再变大

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