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Light and energy

  1. Nov 26, 2005 #1
    Though all EM waves travels in the same speed each one has a diiferent energy. can any one tell me why. i know it is because of planks equation. but i am looking for some logical explanation.
  2. jcsd
  3. Nov 26, 2005 #2


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    Staff Emeritus
    Gold Member

    Naively, you can think of it as an "internal vibration", the speed of which (its frequency) determines the energy of the radiation.
  4. Nov 30, 2005 #3
    yes by the way what happens to the energy of the light when it passes through a different medium pls explain to me in detail.
  5. Nov 30, 2005 #4

    Doc Al

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    Staff: Mentor

    When light passes through a passive medium its frequency (and thus the energy of a photon) remains the same but its wavelength changes.
  6. Nov 30, 2005 #5
    Energy of light rays does not change as it change mediums. the speed of differant frequence light rays are differant in differant mediums and thus the wavelength of differant frequency rays take the appropriate value
  7. Dec 4, 2005 #6
    thanks for the help
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