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> 某物体同时受到三个力作用而做匀减速直线运动，其中F 1与加速度a的方向相同，F 2与速度v的方向相同，F 3与速度v的方向相反，则(　　) A．F1对物体做正功 B．F2对物体做正功 C．F3对物体做负功 D．合外力对物体做负功

问题：

发布时间：2024-09-08

某物体同时受到三个力作用而做匀减速直线运动，其中F ₁与加速度a的方向相同，F ₂与速度v的方向相同，F ₃与速度v的方向相反，则(　　)

A．F₁对物体做正功 B．F₂对物体做正功 C．F₃对物体做负功 D．合外力对物体做负功

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某物体同时受到三个力作用而做匀减速直线运动，其中F 1与加速度a的方向相同，F 2与速度v的方向相同，F 3与速度v的方向相反，则( ) A．F1对物体做正功 B．F2对物体做正功 C．F3对物体做负功 D．合外力对物体做负功

可能感兴趣的题目：

某物体同时受到三个力作用而做匀减速直线运动，其中F ₁与加速度a的方向相同，F ₂与速度v的方向相同，F ₃与速度v的方向相反，则(　　)

A．F₁对物体做正功 B．F₂对物体做正功 C．F₃对物体做负功 D．合外力对物体做负功