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Light clock question

  1. Dec 26, 2011 #1
    Why does the stationary observer see the spaceship light clock traverse a longer distance?

    How can you prove this? I don't understand why he sees the light take a longer path.

    I understand it because you tell me this is so but I don't understand why it actually happens.
  2. jcsd
  3. Dec 26, 2011 #2


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    Can you understand how a ball boncing between the floor and the ceiling would appear to the stationary observer to traverse a longer path than it would to an observer on the spaceship?
  4. Dec 26, 2011 #3
    I can but that still doesn't really answer the question.

    I can actually imagine it both ways. I can imagine looking at the moving observer and seeing his ball bounce directly up and down. I can also imagine it taking the longer path.

    Would a ball actually take a longer path in reality?

    I want to know why light takes a longer path.
  5. Dec 26, 2011 #4


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    Yes, the way you can imagine it both ways are two different ways you can describe the motion of the ball and the light which would be identical to two different Frames of Reference.
  6. Dec 26, 2011 #5
    there is no 'reality' only 'relativity'
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