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> 在正常情况下，火车以54km/h的速度匀速开过一个小站．现因需要，必须在这一小站停留，火车将要到达小站时，以-0.5m/s 2的加速度做匀减速运动，停留2分钟后，又以0.3m/s 2的加速度出小站，一直到恢复原来的速度．求因列车停靠小站而延误的时间．

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发布时间：2024-09-08

在正常情况下，火车以54km/h的速度匀速开过一个小站．现因需要，必须在这一小站停留，火车将要到达小站时，以-0.5m/s ²的加速度做匀减速运动，停留2分钟后，又以0.3m/s ²的加速度出小站，一直到恢复原来的速度．求因列车停靠小站而延误的时间．

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