問題詳情
21.假设地球是一半径为R、质量分布均匀的球体。一矿井深度为d。已知质量分布均匀的球壳对壳内物体的引力为零。矿井底部和地面处的重力加速度大小之比为 
(A)
(B)
(C)
(D)
(A)
(B)
(C)
(D)
參考答案
答案：A
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)
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