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Harmful radiation

  1. Dec 8, 2004 #1

    If one travels fast enough against it, will a regular photon of visual wavelength become harmful due to the doppler effect?
  2. jcsd
  3. Dec 8, 2004 #2
    hmm, interesting.

    wonder how fast you'd have to go to blue-shift a light photon into a UV or x-ray photon. should be simple enough to calculate. The answer should tell you if it's possible or not.
  4. Dec 8, 2004 #3


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    ordinary sunlight is around 2 eevee and Xray is around 1000 eevee.

    so you just need a speed beta which makes the doppler ratio be around 500. Here is the relativistic doppler formula, squared both sides to make it easier to write.

    250000 = (1+beta)/(1-beta)

    if you solve this for beta you get
    beta = 249999/250001

    so that is what fraction of the speed of light you would have to go
    in order to boost the photon energy by a factor of 500

    but well before that it would be harmful
    Last edited: Dec 8, 2004
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