试题与答案

如图所示,一质量为0.5 kg的圆环沿竖直放在地面上的直杆匀速下滑,则圆环受到的

题型:填空题

题目:

如图所示,一质量为0.5 kg的圆环沿竖直放在地面上的直杆匀速下滑,则圆环受到的摩擦力为_____,方向是_____,这是根据_____的知识分析判断的.(g取10 N/kg)

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B

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