试题与答案

如下图所示,让摆球从图中的C位置由静止开始摆下,摆到最低点D处,摆线刚好被拉断,

题型:计算题

题目:

如下图所示,让摆球从图中的C位置由静止开始摆下,摆到最低点D处,摆线刚好被拉断,小球在粗糙的水平面上由D点向左做匀减速运动,到达A孔进入半径R=0.3m的竖直放置的光滑圆弧轨道,当摆球进入圆轨道立即关闭A孔。已知摆线长L=2m,,小球质量为m=0.5kg,D点与小孔A的水平距离s=2m,g取10m/s2。试求:

(1)求摆线能承受的最大拉力为多大?

(2)要使摆球能进入圆轨道并且不脱离轨道,求粗糙水平面摩擦因数μ的范围。

答案:

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