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Change In energy due to Doppler shift

  1. Aug 15, 2013 #1
    Hello all, so lets suppose a photon is being gravitationally red or blue shifted changing its frequency which ultimately changes its energy, where does this energy change come from?
  2. jcsd
  3. Aug 15, 2013 #2


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    I believe it's from the potential energy of the system. (Photon + object attracting it)
    The photon gains energy and the system loses an equal amount of potential energy or vice versa.
  4. Aug 15, 2013 #3

    Vanadium 50

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    Suppose a drop a ball in a gravitational field and it gains kinetic energy. Where does this energy change come from?
  5. Aug 15, 2013 #4
    Thankyou all, answers were very helpful
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