We can plug this in further when we're talking about the visible part of the light spectrum, because we know that for n final equals 2, then that would mean we plug in 2 squared here, so what we get is 1 over 4.

当我们讨论可见光谱的时候,我们可以把这个代进去,因为我们知道n末是等于2的,这意味着我们可以。

麻省理工公开课 - 化学原理课程节选

So this is our final equation, and this is actually called the Balmer series, which was named after Balmer, and this tells us the frequency of any of the lights where we start with an electron in some higher energy level and we drop down to an n final that's equal to 2.

把2代入到这里，所以得到1除以,这就是我们最终的方程，这叫做Balmer系，以Balmer名字命名的,它告诉我们从高能级掉到n等于2的,最终能级所发出光的频率。

麻省理工公开课 - 化学原理课程节选

It just turns out that if you put the v^2 and you put the r, and r is 93 million miles, you will find the acceleration is small enough for us to ignore.

这样的话,如果你把 v^2 和 r 代进去,r 是 9300 万英里,你会发现加速度小得足以被忽略

耶鲁公开课 - 基础物理课程节选