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Homework Help: Relativity nightmare

  1. Oct 29, 2009 #1


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    i cant understand the graph.

    i know that its time and x axes graph

    but i can imagine the pole moving
    or the barn moving to the runner

    all i see is some lines

    the part when the barn moving to the runner is the hardest graph

    i dont know what happening there
  2. jcsd
  3. Nov 1, 2009 #2


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    Hi lom! :smile:

    it's like two trains on adjacent track …

    you're on one train, looking at the other, and you can't tell which train is moving.

    Here, the barn is one train, and the runner is the other train.

    You can regard the runner as stationary, and in that case the barn must be moving.

    Since they're getting closer (well, until he gets inside! :rolleyes:), that means the barn must be moving backwards. :smile:

    (and world-lines always slope towards the direction of motion)
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