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Objects and stationary observers

  1. Jul 13, 2003 #1


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    An object moves in a direction parallel to its length with a velocity that approaches the velocity of light. The width and length of this object, as measured by a stationary observer is what?

    Can anyone gimme more insight on this problem. Im having difficulties understanding just what the hell they are talking about.
    does the width approach zero while the length approaches infinity.
    Dx [zz)]
  2. jcsd
  3. Jul 14, 2003 #2
    Only the dimension in which motion is will change, that is length.
    It will get smaller by the factor Sqrt(1-(v2/c2)).
    So :
    Lseen by observer=Loriginal*sqrt(1-(v2/c2))

    Of course, if you wait for an expert to confirm this it would be better.
  4. Jul 19, 2003 #3


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    Ok! Just to make sure I am on the right track then. The width does not change but the length approaches zero because a length of an object is measured to be shorter when its moving relative to the observer than at rest.

    Yeah? I think I finally got it.

    Dx :wink:
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