某一物体做变速直线运动，已知它在前一半路程中的速度是4 m/s ，后一半路程中的速度是6 m/s，那么它在整个路程中的平均速度是（）_刷题宝

题干

某一物体做变速直线运动，已知它在前一半路程中的速度是4 m/s ，后一半路程中的速度是6 m/s，那么它在整个路程中的平均速度是（）

A：4 m/s

B：4．8 m/s

C：5 m/s

D：6 m/s

上一题下一题 0.0难度选择题更新时间:2014-09-26 05:46:59

答案(点此获取答案解析）

B

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