If you multiply entry 23, which is 13.6 electron volts I will show you what the electron volt is in a few minutes. We will just put it up here prematurely. But that is given in your chart.

如果乘上第23个常量，代表13。6电子伏,接下来我就会向你们说明什么是电子伏,我们先提前把它提出来,但那只是放在你们的图表中。

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Once you do that, I think it's fairly clear that it has got a y component that's given by cosine the x component is negative.

用了这个结论,我想很明显,y 分量由 cos φ 给出,它的 x 分量是负的

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