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> 以v 0 ="12" m/s的速度匀速行驶的汽车，突然刹车，刹车过程中汽车以a =－6 m/s 2的加速度继续前进，则刹车后( ) A．3 s内的位移是9 m; B．3 s内的位移是12 m; C．3s末的速度是－6 m/s; D．3 s末的速度是0m/s.

问题：

发布时间：2024-09-09

以v ₀="12" m/s的速度匀速行驶的汽车，突然刹车，刹车过程中汽车以a =－6 m/s ²的加速度继续前进，则刹车后( )

A．3 s内的位移是9 m; B．3 s内的位移是12 m;

C．3s末的速度是－6 m/s; D．3 s末的速度是0m/s.

参考答案：

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