来自《耶鲁大学开放课程：新生有机化学 第2集 第2集》

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  and now you'd have more things hitting the moon
  原本来自左边的推力被地球阻滞
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  from the right than from the left.
  从右面作用于月球的推力就会多于左边
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  So it would seem to be attracted to the earth.
  所以月球就会被地球吸引
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  So that's a great mechanism.
  这是个伟大的理论
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  Now, it was important for Newton
  不过牛顿的重点在于
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  that the force be proportional to r^2, to inverse r^2, 1/r^2.
  这个力的大小正比于1/r^2
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  Does this work for that?
  这和笛卡尔的理论抵触吗
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  If you pulled the earth back, how would you change things?
  如果将地球向后拉 会有什么变化呢
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  What do you say?
  你觉得呢
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  Student: I don't know. It doesn't work for this.
  不知道 这说不通
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  Prof: It doesn't work?
  说不通吗
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  Would it block more or fewer things if you pulled it back?
  被地球挡住的力会增加还是减少呢