3.某人造地球卫星因受高空稀薄空气的阻力作用,绕地球运转的轨道

3.某人造地球卫星因受高空稀薄空气的阻力作用,绕地球运转的轨道会慢慢改变,每次测量中卫星的运动可近似看作圆周运动.某次测量卫星的轨道半径为r1,后来变为r2,r2<r1

.以Ek1、Ek2表示卫星在这两个轨道上的动能,T1、T2表示卫星在这两个轨道上绕地运动的周期,则

(不定项选择题)

A. Ek2<Ek1,T2>T1

B. Ek2>Ek1,T2<T1                                                 

C. Ek2<Ek1,T2<T1                                                           

D. Ek2>Ek1,T2>T1

答案

C

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