试题与答案

如图所示,ABCO是处于竖直面内的光滑轨道,其中AB是半径R=15m的1/4圆周

题型:计算题

题目:

如图所示,ABCO是处于竖直面内的光滑轨道,其中AB是半径R=15m的1/4圆周轨道,半径OA处于水平位置;BCO是半径为r=7.5m的半圆轨道,C是半圆轨道的中点。质量为m=300g的小球P从A点正上方高h=10m处的D点自由落下,进入光滑轨道中。求:

(1)小球到达C点时对轨道的压力N的大小;

(2)小球能否到达O点?若能到达,小球通过O点后再次落到AB轨道上时的速度v多大?

答案:

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