试题与答案

(10 分)地球质量为M、半径为R,万有引力常量为G,发射一颗绕地球表面附近做圆

题型:计算题

题目:

(10 分)地球质量为M、半径为R,万有引力常量为G,发射一颗绕地球表面附近做圆周运动的人造卫星,卫星的速度称为第一宇宙速度.

(1)试推导由上述各量表达的第一宇宙速度的计算式;

(2)若已知第一宇宙速度的大小v="7.9" km/s,地球半径R=6.4×103 km,万有引力常量G=6.7×10-11 N·m2/kg2,求地球质量(结果保留两位有效数字).

答案:

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参考答案:A

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