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力的合成

> 关于运动的合成与分解，下列几种说法正确的是（　　） A．物体的两个分运动是直线运动，则它们的合运动一定是直线运动 B．若两个分运动分别是匀速直线运动和匀加速直线运动，则合运动可能是曲线运动 C．两个分运动的时间一定与它们合运动的时间相等 D．速度、加速度和位移的合成都遵循平行四边形定则

问题：

发布时间：2024-09-09

关于运动的合成与分解，下列几种说法正确的是（　　）

A．物体的两个分运动是直线运动，则它们的合运动一定是直线运动

B．若两个分运动分别是匀速直线运动和匀加速直线运动，则合运动可能是曲线运动

C．两个分运动的时间一定与它们合运动的时间相等

D．速度、加速度和位移的合成都遵循平行四边形定则

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