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> （15分）一辆轿车违章超车，以108 km/h的速度驶入左侧逆行道时，猛然发现、正前方80 m处一辆卡车正以72 km/h的速度迎面驶来，两车司机同时刹车，刹车加速度大小都是10 m/s 2，两司机的反应时间(即司机发现险情到实施刹车所经历的时间)都是Δ t.试问Δ t是何数值，才能保证两车不相撞?

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发布时间：2024-09-09

（15分）一辆轿车违章超车，以108 km/h的速度驶入左侧逆行道时，猛然发现、正前方80 m处一辆卡车正以72 km/h的速度迎面驶来，两车司机同时刹车，刹车加速度大小都是10 m/s ²，两司机的反应时间(即司机发现险情到实施刹车所经历的时间)都是Δ t.试问Δ t是何数值，才能保证两车不相撞?

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