问题
选择题
银河系的恒星中大约四分之一是双星.某双星由质量不等的星体S1和S2构成,两星在相互之间的万有引力作用下绕两者连线上某一定点C做匀速圆周运动. 由天文观测得其周期为T,S1到C点的距离为r1,S1和S2的距离为r,已知万
有引力常量为G.由此可求出S2的质量为（ ）
A．
B．
C．
D．
答案
答案：D
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银河系的恒星中大约四分之一是双星.某双星由质量不等的星体S1和S2构成,两星在相互之间的万有引力作用下绕两者连线上某一定点C做匀速圆周运动. 由天文观测得其周期为T,S1到C点的距离为r1,S1和S2的距离为r,已知万有引力常量为G.由此可求出S2的质量为（ ）
A．
B．
C．
D．
答案：D
| 阅读理解。 | ||||
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| A. 19:00 on CCTV-1 Channel 2 B. 20:05 on CCTV-1 Channel 2 C. 22:00 on CCTV-2 Channel 8 D. 21:30 on CCTV-2 Channel 8 | ||||
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