1.减小物体间的压力,如人拉空箱子比拉装满东西的箱子要容易
2.减小接触面的粗糙程度,如往自行车链条中滴润滑油
3.用滑动摩擦代替滚动摩擦,如轴承里的滚珠
4.使两个相互接触的摩擦面彼此分离,如气垫船
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