This found that if the reverse idea of the electron charge-mass ratio as a known quantity, it can re-theoretical derivation, and thus obtain the value of the vacuum in the speed of light.

笔者发现，如果进行逆向构思，把电子的荷质比作为已知量时，可重新进行理论推导从而得到真空中的光速值。

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By use of magnetic balance which is general physical experiment instrument, a simple and new method of measuring the charge-mass ratio of electron mass developed.

使用常用物理实验仪器磁天平，开发出用于近代物理实验测量电子荷质比的简易新方法。

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He measured the charge to mass ratio of the electron.

他测量了电子的荷质比。

麻省理工公开课 - 固态化学导论课程节选