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匀变速直线运动

> 一火车以2 m/s的初速度，0.5 m/s 2的加速度做匀加速直线运动，求： （1）火车在第3 s末的速度是多少？ （2）在前4 s的平均速度是多少？ （3）在第5 s的位移是多少？ （4）在4 s内的位移是多少？

问题：

发布时间：2024-09-08

一火车以2 m/s的初速度，0.5 m/s ²的加速度做匀加速直线运动，求：
（1）火车在第3 s末的速度是多少？
（2）在前4 s的平均速度是多少？
（3）在第5 s的位移是多少？
（4）在4 s内的位移是多少？

参考答案：

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