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Homework Help: Balmer's Formula.

  1. Apr 16, 2008 #1
    [SOLVED] Balmer's Formula.

    1. I am to find the formula of each series of wavelengths:
    • 12500, 31.25, 13.90, 7.81, and 5.00 nm
    • 375, 900, 1575, 2400, 3375, and 4500 nm
    ***Also, n might not always equal 1.




    2. [tex]\lambda[/tex] = [tex]\frac{94.18 nm} ({\frac{1}{m^{2}}) - (\frac{1}{n^{2}})}[/tex])
    Where m = 1, 2, 3, ... and n = m+1, m+2, ...​




    3. My prof said that all I had to do was plug and chug, but I am not exactly sure what she meant by that, and do I assume that m is just zero at times?
    I want to know if there is a way I can do this mathematically? She told me to THINK squares, so I attempted to take the square root of the numbers.

    Any guidance will be appreciated.
     
  2. jcsd
  3. Apr 16, 2008 #2
    I wanted to clarify since I seem to have found the second one, it is talking about finding a FORMULA, so Balmer's formula is really useless in a way.

    If a Mod would rename this I would really appreciate it, rename it to: Finding Formula given a series.
     
  4. Apr 16, 2008 #3
    And I just figured out the second one, what a waste of forum-space!

    Thanks anyway!

    :D
     
  5. Apr 16, 2008 #4
    One way is to take differences between succesive numbers, and see if a pattern emerges.
    Take the differences of the differences is that doesn't work. If the differences are constant after n steps the numbers can be produced with a n'th degree polynomial.

    since the numbers are wavelengths, you could try the frequencies as well.

    I think the first number from a needs to be 125.00
     
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