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匀变速直线运动

> 如图所示，选沿斜面向上为正方向，小球以v 0=20m／s、加速度为a=-5m／s 2,从A点沿光滑斜面一直做匀变速直线运动，斜面长L=40m．求小球经过斜面中点C需要的时间( ) A．2s B．6.828s C．2.586s D．1.172s

问题：

发布时间：2024-09-07

如图所示，选沿斜面向上为正方向，小球以v ₀=20m／s、加速度为a=-5m／s ²,从A点沿光滑斜面一直做匀变速直线运动，斜面长L=40m．求小球经过斜面中点C需要的时间( )

A．2s B．6.828s C．2.586s D．1.172s

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