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Homework Help: Cant calculate?

  1. May 11, 2012 #1
    1. The problem statement, all variables and given/known data

    My book has a problem with a solution in which:

    2.55 eV/4.14 x 10^-15 eVs = 6.16 x 10^ 14 Hz.

    My question is:

    I am trying to figure out why the answer is 10^14 when before they had 10^-15??
     
    Last edited: May 11, 2012
  2. jcsd
  3. May 11, 2012 #2

    gneill

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    Staff: Mentor

    What's 2.55/4.14? Express it in scientific notation.
     
  4. May 11, 2012 #3
    2.55/4.14 = 0.616 approximately.
    Then I say 6.16 x 10^-1
     
  5. May 11, 2012 #4
    10^-1 x 10^-15 = 10^-16 not 10^14 as my book says.
     
  6. May 11, 2012 #5

    gneill

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    Staff: Mentor

    Correct.
    But the 10-15 is in the denominator. What happens to it when you 'promote' it to the numerator?
     
  7. May 11, 2012 #6
    :rofl::biggrin:ooooooooooooohhh I got it.
    Thank you!!!:blushing:
     
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