(adsbygoogle = window.adsbygoogle || []).push({}); 1. A monochromatic laser is exciting hydrogen atoms from the n = 2 state to the n = 5 state. What is the wavelength of the laser?

2. frequency = f = delta E / h

lambda = c/f

3. First, is the following approach valid:

I find delta E by computing E_{5}- E_{2}, where E_{n}= n^{2}h^{2}/8mL^{2}

I then divide that answer by h to obtain f, then do c/f = lambda.

If that's a valid approach, then I am confused as to what I use for L in the E_{n}formula.

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# Homework Help: Wavelength of a laser exciting H atom from n =2 to n = 5

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