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匀变速直线运动

> 火车在平直轨道上做匀变速直线运动，经过时间t，它的速度由变为，经过的位移为x，下列说法正确的是( ) A．这段时间内的平均速度等于x/t B．这段时间内的平均速度等于 C．经过t/2，它的瞬时速度是x/t D．经过x/2，它的瞬时速度是

问题：

发布时间：2024-09-12

火车在平直轨道上做匀变速直线运动，经过时间t，它的速度由变为，经过的位移为x，下列说法正确的是( )

A．这段时间内的平均速度等于x/t B．这段时间内的平均速度等于

C．经过t/2，它的瞬时速度是x/t D．经过x/2，它的瞬时速度是

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