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。

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