问题 计算题

如图所示,半径2R四分之一圆弧与半径为R的光滑半圆在B点相连接,C与A点等高,一个质量为m的小球从A点由静止释放,恰好到达与圆心O等高的D点。求:

(1)摩擦力对小球所做的功是多少?

(2)假设AEB段摩擦力做功不变,小球刚过B点时对轨道的压力是多少?

(3)假设AEB段摩擦力做功不变,在A点给小球不同的速度,它将始终不脱离轨道运动,并能通过C点做平抛运动,当落点E到C点的竖直距离最大时,求A点的速度v0是多少?

答案

阅读理解

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