If you take the Earth itself around the sun because we can use all these equations replace the mass of the Earth by the mass of the sun, and then we can do this for planets.

如果你算地球绕太阳，因为我们用所有这些，等式，以太阳质量，代替地球质量，然后我们再用行星做。

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Thee Internet is so penetrating in people's lives that many people believe it will replace the traditional mass media in the near future.

互联网在人们生活中的渗透，许多人认为它将取代传统的大众传媒在不久的将来。

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Now I replace this object by mass m2 but the extension is the same, so the pull must be same the spring doesn't know what the mass is at the other end, right?

再以质量m2的物体做同一个实验2，弹簧伸长相同，可知拉力相同，这与悬挂物体的质量，无关？

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