He measured the charge to mass ratio of the electron.

他测量了电子的荷质比。

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But the acceleration it produces on the elephant and on the mass, are in an inverse ratio of their masses.

但这个力使大象和物体产生的加速度,与它们的质量成反比

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That is why we don't worry about the motion of the nucleus 1 because the ratio of mass is about 2,000 to one.

这就解释了为什么我们不担心,原子核运动起来,因为原子核和电子的质量比约为2000：

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