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质量为3kg的物体静止在水平地面上,现用水平力F作用5s后撤去,物体运动的速度图象如图,则物体与水平地面间的动摩擦因数μ=                                                                           ,水平力F=                N.(取g=10m/s2)   

                                                                                 

                                                                                                                               

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