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SR problem

  1. Nov 1, 2007 #1
    why we do not observe any “lack of simultaneity” when we substitute sound signals for the light flashes in the “thought experiment” with a train moving past a platform (Einstein's lightning strike-train "thought experiment")?

    this has troubled me for 5hours now. i dont know whether it is too advanced a question for me or whether i am blind to the answer.

    can anyone help?

    thanks :smile:
  2. jcsd
  3. Nov 1, 2007 #2
    All observers measure the same value for the speed of light, but they measure the speed of sound to depend on their velocities relative to the air.
  4. Nov 2, 2007 #3
    the addition of velocities theorem was part of the reason for my confusion. i couldnt understand why simultaneity occurs when the sound signals are used? surely the observer in the reference frame moving at around c wouldnt hear the sound signal emitted from the point behind he/she?
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