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匀变速直线运动

> 沿直线做匀加速运动的质点在第一个0.5s内的平均速度比它在第一个1.5 s内的平均速度大2.45 m/s，以质点的运动方向为正方向，则质点的加速度为 A．2.45 m/s2 B．－4.90 m/s2 C．4.90 m/s2 D．－2.45 m/s2

问题：

发布时间：2024-09-10

沿直线做匀加速运动的质点在第一个0.5s内的平均速度比它在第一个1.5 s内的平均速度大2.45 m/s，以质点的运动方向为正方向，则质点的加速度为

A．2.45 m/s² B．－4.90 m/s²

C．4.90 m/s² D．－2.45 m/s²

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