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匀变速直线运动

> 一物体以初速度为v 0做匀减速运动,第1s内通过的位移为x 1=3m ,第2s内通过的位移为x 2=2m,又经过位移x 3物体的速度减小为0,则下列说法中不正确的是 A．初速度v0的大小为2.5m/s B．加速度a的大小为1m/s2 C．位移x3的大小为9/8m D．位移x3内的平均速度大小为0.75m/s

问题：

发布时间：2024-09-08

一物体以初速度为v ₀做匀减速运动,第1s内通过的位移为x ₁=3m _,第2s内通过的位移为x ₂=2m,又经过位移x ₃物体的速度减小为0,则下列说法中不正确的是

A．初速度v₀的大小为2.5m/s

B．加速度a的大小为1m/s²

C．位移x₃的大小为9/8m

D．位移x₃内的平均速度大小为0.75m/s

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