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匀变速直线运动

> 静止在水平面上的物体的质量为2 kg，在水平恒力F推动下从静止开始做匀加速直线运动，4 s末它的速度达到4 m/s，此时将F撤去，物体做匀减速直线运动，又经6 s物体停下来，如果物体与地面的动摩擦因数不变，求：（1）前4s内的加速度；（2）前4s内的位移；（3）F的大小．

问题：

发布时间：2024-09-07

静止在水平面上的物体的质量为2 kg，在水平恒力F推动下从静止开始做匀加速直线运动，4 s末它的速度达到4 m/s，此时将F撤去，物体做匀减速直线运动，又经6 s物体停下来，如果物体与地面的动摩擦因数不变，求：
（1）前4s内的加速度；
（2）前4s内的位移；
（3）F的大小．

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