作自由落体运动的物体,先后经过空中M、N两点时的速度分别为v

作自由落体运动的物体,先后经过空中M、N两点时的速度分别为v1和v2,则下列说法中正确的是(   )

A.MN间距离为                   B.经过MN的平均速度为

C.经过MN所需时间为        D.经过MN中点时速度为

答案

ABC


解析:

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