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近地卫星和同步卫星

> 如图所示，a、b、c是地球大气层外圆形轨道上运行的三颗人造地球卫星，下列说法中正确的是 A．b、c的线速度大小相等，且大于a的线速度 B．b、c的向心加速度大小相等，且小于a的向心加速度 C．b、c的运行周期相同，且小于a的运行周期 D．若b速度增大，会与c相碰

问题：

发布时间：2024-09-10

如图所示，a、b、c是地球大气层外圆形轨道上运行的三颗人造地球卫星，下列说法中正确的是

A．b、c的线速度大小相等，且大于a的线速度

B．b、c的向心加速度大小相等，且小于a的向心加速度

C．b、c的运行周期相同，且小于a的运行周期

D．若b速度增大，会与c相碰

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