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速度与机械运动

> 下列关于摩擦的说法中，正确的是 A.接触面积越大，物体运动速度越小，所受摩擦力越大 B.摩擦力的方向总是跟物体运动方向相反 C.收音机旋钮上所刻花纹是为了减小摩擦 D.汽车刹车过程中，地面对汽车的摩擦是有益的

问题：

发布时间：2024-09-09

下列关于摩擦的说法中，正确的是

A.接触面积越大，物体运动速度越小，所受摩擦力越大
B.摩擦力的方向总是跟物体运动方向相反
C.收音机旋钮上所刻花纹是为了减小摩擦
D.汽车刹车过程中，地面对汽车的摩擦是有益的

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