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Periods of waves

  1. Feb 24, 2010 #1
    1. The problem statement, all variables and given/known data
    Light waves have very high frequencies compared to sound. The frequency for red light is about 4.6x10^14Hz and for blue 7.0x10^14Hz. What are the periods of these two waves?

    2. Relevant equations


    3. The attempt at a solution
    I used the equation above which is correct in my understanding is this correct?
    For Red light i had an answer of 2.173913043x10^-15. I am not sure if this is right so if someone could help me.
    If it does seem to be correct how would i write it down as a answer. E.G
    The period for red light =2.173913043x10^-15 (S)

    I know sounds stupid but just want to be clear.
    Thanks in advance
  2. jcsd
  3. Feb 24, 2010 #2
    The equation is fine and the answer is correct.
    All you need to do is lose some of those decimal places.
    Give your answer to the same precision (significant figures) as the data in the question.
    You were given the frequency to 2 significant figures (4.6 x 10^14) so give your answer to the same number.
    Do the same for the blue light.
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