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如图所示,ABCD是一个盆式容器,盆内侧壁与盆底BC的连接处都是一段与BC相切的圆弧,B、C是水平的,其距离 d=0.50 m,盆边缘的高度为h=0.30 m.在A处放一个质量为m的小物块并让其从静止出发下滑.已知盆内侧壁是光滑的,而盆底BC面与小物块间的动摩擦因数为μ=0.40.小物块在盆内来回滑动,最后停下来,则停的地点到C的距离为多少?

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解:设小物块在BC面上运动的总路程为S,物块在BC面上所受的滑动摩擦力大小始终为f=μmg,对小物块从开始运动到停止运动的整个过程进行研究,由动能定理得
mgh−μmgS=0
得到S=
h
μ
=

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