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匀变速直线运动

> （8分）摩托车从A点由静止出发做匀加速直线运动，用7 s时间通过一座长BC＝14 m的平桥，过桥后的速度是3 m/s。 (1)它刚开上桥头时的速度v B有多大？ (2)桥头与出发点相距多远？

问题：

发布时间：2024-09-12

（8分）摩托车从A点由静止出发做匀加速直线运动，用7 s时间通过一座长BC＝14 m的平桥，过桥后的速度是3 m/s。
(1)它刚开上桥头时的速度v _B有多大？
(2)桥头与出发点相距多远？

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