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Homework Help: What is the index of refraction of this substance?

  1. Apr 8, 2010 #1
    The speed of light in a certain substance is 79.0% of its value in water.
    What is the index of refraction of this substance?


    Here's what I've done so far:

    (3.0*10^8 m/s)(0.79) because its 79%.
    In water, the n=1.003.

    I'm not sure where to go from there.
    Any help would be greatly appreciated!
    Thanks in advance.
     
  2. jcsd
  3. Apr 8, 2010 #2

    Redbelly98

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    No, that's n for air.
    n for water is ____?
    The speed of light in water is ____?
     
  4. Apr 9, 2010 #3
    correction:
    n=1.33
    and the speed of light in water (3x10^8)/(1.33)=2.25x10^8
     
  5. Apr 9, 2010 #4

    Redbelly98

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    That's right. And:
    Hope that's enough.
     
  6. Apr 9, 2010 #5
    Since 79%, mulitplying (2.26x10^8)(0.79)= 1.78x10^8.
    Correct?
     
  7. Apr 9, 2010 #6

    Redbelly98

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