【题目描述】
【我提交的答案】:
【参考答案分析】:
要想相遇:A球做平抛运动,水平方向匀速直线运动:vA*t=s① 竖直方向A球自由落体:½gt²=h 时间t²<=(2*h)/g② 由①②可知:当t取最大值时,v取最小值vmin=s/t(max)=s*sqrt(g/2h)由于A B两球运动的时间相同,所以vA:vB=(vA*t):(vB*t)=s:h

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