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What is the frequency (in Hz) of infared radiation that has a wavelength of 160.432 m

  1. Dec 12, 2009 #1
    1. The problem statement, all variables and given/known data

    What is the frequency (in Hz) of infared radiation that has a wavelength of 160.432 micrometers? The speed of light is 3.00 x 108 m/s.

    2. Relevant equations

    Speed of light = wavelength x frequency

    Speed of light = 3.00 x 10^8 m/s

    3. The attempt at a solution

    I know that the speed of light is equal to wavelength multiplied by frequency and that this question is basically just plug and chug. But I keep getting the wrong answer. What I did is I converted 160.432 micrometers into meters, which is 1.60432 x 10-4. Then I divided 3 x 108 (m/s) by 1.60432 x 10-4 (m). I get the value of 1.86995 x 1012. I convert this value to nanometers: 1.86 x 1021. This is the wrong answer! What did I do wrong?
     
  2. jcsd
  3. Dec 12, 2009 #2

    diazona

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    Re: What is the frequency (in Hz) of infared radiation that has a wavelength of 160.4

    What units are missing from your value 1.86995 x 1012? Figure that out and you may notice where you went wrong.
     
  4. Dec 12, 2009 #3
    Re: What is the frequency (in Hz) of infared radiation that has a wavelength of 160.4

    I think I figured it out: [3 x 108 (m/s)/ 160.432 micrometers] x [106 micrometers/ 1 meter] = 1.869951132 x 10^12

    Could you reply back and check if this is the right answer because I think I have only one more shot at getting this right on my online homework.
     
  5. Dec 12, 2009 #4

    diazona

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    Re: What is the frequency (in Hz) of infared radiation that has a wavelength of 160.4

    Again, you're missing the units from your answer. But assuming the missing unit is Hz (as the problem requests), you seem to have done it correctly.
     
  6. Dec 12, 2009 #5
    Re: What is the frequency (in Hz) of infared radiation that has a wavelength of 160.4

    I went ahead and checked it. I got it right. Thank you.
     
  7. Dec 12, 2009 #6
    Re: What is the frequency (in Hz) of infared radiation that has a wavelength of 160.4

    Such a conversion adds another possible occasion to make a mistake. I would enter 160.432 X 10-6 into the calculator.
     
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