物体由斜面顶端由静止开始下滑,经过斜面中点时速度为2m/s,则物体到达斜面底端时的速度为( )_刷题宝

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物体由斜面顶端由静止开始下滑,经过斜面中点时速度为2m/s,则物体到达斜面底端时的速度为( )

A：3m/

B：4m/

C：6m/

D：m/

上一题下一题 0.0难度选择题更新时间:2014-03-29 10:52:09

答案(点此获取答案解析）

D

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You are only three years.old,and at this point in your life you are not able to understand this letter.But some day when you1,I hope you will find something2in what I am going to share with you.

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