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近地卫星和同步卫星

> “嫦娥一号”飞船在飞往月球的过程中，经过多次变轨，先后在低空 A轨道和高空 B轨道绕地球做圆周运动，如图所示．不考虑月球对它的作用力，则“嫦娥一号”在 A轨道运行时： A．线速度大于7.9km/s B．线速度比在B轨道的大 C．周期比在B轨道的长 D．所需向心力比在B轨道的大

问题：

发布时间：2020-03-13

“嫦娥一号”飞船在飞往月球的过程中，经过多次变轨，先后在低空 A轨道和高空 B轨道绕地球做圆周运动，如图所示．不考虑月球对它的作用力，则“嫦娥一号”在 A轨道运行时：

A．线速度大于7.9km/s

B．线速度比在B轨道的大

C．周期比在B轨道的长

D．所需向心力比在B轨道的大

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