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> 一辆汽车以72km/h的速度正在平直公路上匀速行驶，突然发现前方40m处有需要紧急停车的危险信号，司机立即采取刹车措施．已知该车在刹车过程中加速度的大小为5m/s 2，则从刹车开始经过5s时汽车前进的距离是多少？此时是否已经到达危险区域？

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发布时间：2024-09-12

一辆汽车以72km/h的速度正在平直公路上匀速行驶，突然发现前方40m处有需要紧急停车的危险信号，司机立即采取刹车措施．已知该车在刹车过程中加速度的大小为5m/s ²，则从刹车开始经过5s时汽车前进的距离是多少？此时是否已经到达危险区域？

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