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Ok is there a differnce in.

  1. Nov 5, 2005 #1
    Ok is there a differnce in.........

    Ok is there a differnce in speed when dealing with blue light and yellow light in air. I have tried read the doppler effect over and over, but so All I can see pertaining to is that one color indicates an object moving away and one moving towards. Light is light isn't it???
     
  2. jcsd
  3. Nov 5, 2005 #2

    Danger

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    Light is simply the visible and near-visible section of the electromagnetic spectrum, which includes everything from extremely long radio waves up to highest frequency gamma. It all consists of photons with an oscillating electric field and an accompanying magnetic one. The colour is determined by the frequency. Red is low, blue is high.
     
  4. Nov 5, 2005 #3
    So the frequency of differnt color light doesn't effect the speed at which these colors of light travel.? Becuase 2 differnt colors of light in the same medium wil travel at the same speed..Right????

    One other question. What is a wave period. Is it the same as the wave length???
     
    Last edited: Nov 5, 2005
  5. Nov 5, 2005 #4

    Danger

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    Frequency determines the propogation rate (which Zapper properly referred to as the 'group velocity') through a medium, but not the speed of the photons themselves. I've never actually heard the term 'period' used in regard to EM radiation. I suspect that it means the time required for one complete oscillation of the EM field (one second divided by the frequency).
     
  6. Nov 5, 2005 #5
    wave period, say when dealing with ocean waves.
     
  7. Nov 5, 2005 #6

    Danger

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    I'm afraid that you're outrunning me here. :redface:
    Best if someone else takes over.
     
  8. Nov 5, 2005 #7

    krab

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    right
    period is reciprocal of frequency. Wavelength is period times speed.
     
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