题干

如图,两木块A和B被水平力F通过挡板C压在竖直墙上,处于静止状态,则(   )

A:物体A对B没有摩擦力

B:物体A对B的静摩擦力方向竖直向上

C:物体A对B的静摩擦力方向竖直向下

D:条件不足,无法判断

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答案(点此获取答案解析)

C

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                                                                                   就是那一只蟋蟀
                                                                                   在海峡那边唱歌
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                                                                                   比最单调的乐曲更单调
                                                                                   比最和谐的音响更谐和
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                                                                                   我在吟哦
                                                                                   你该猜到我在吟些什么
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