Question

a、b为完全相同的截面为直角楔形物体，分别在垂直于斜边的恒力F1、F2 作用

1．a、b为完全相同的截面为直角楔形物体，分别在垂直于斜边的恒力F1、F2 作用下静止在相同的竖直墙面上，如图所示．下列说法正确的是.B A．a、b 受力个数一定相等 B．b 受到摩擦力小于 a 受到的摩擦力 C．a、b 所受摩擦力方向一定沿墙面向上 D．F1、F2 大小一定相等
答案是B，但是万一F2非常大，使得摩擦力向下与重力一起平衡F2向上的分力，此时可能会出现b的摩擦力大于a的摩擦力不是吗？且题中没给出最大静摩擦力，因此是有可能的。

Answer 1

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