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Homework Help: Spatial Separation

  1. Sep 16, 2010 #1
    1. The problem statement, all variables and given/known data

    Two events occur at the same place in a certain inertial frame and are separated by a time interval of 4 seconds. What is the spatial separation between these two events in an inertial frame in which the events are separated by a time interval of 6 seconds?

    2. Relevant equations

    Lorentz Transforms

    3. The attempt at a solution

    I really have no idea where to start. I know its not that hard I am just drawing a blank
     
  2. jcsd
  3. Sep 16, 2010 #2

    gabbagabbahey

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    Hint: What quantity involving both time and position is invariant under Lorentz transforms?
     
  4. Sep 16, 2010 #3
    I know the speed of light is invariant. The way I worked it was putting it through the Lorentz time transform solving for v. then put that v in the x Lorentz transform
     
  5. Sep 16, 2010 #4

    gabbagabbahey

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    Sure, [itex]c[/itex] is Lorentz invariant, but it doesn't invole time or position, so that doesn't help. What about the spacetime interval [itex]\delta s^2[/itex]?
     
  6. Sep 16, 2010 #5
    Could you give me maybe a walk through on how to find that or even the problem. I am really at a loss, I missed a week of classes because i was sick.
     
  7. Sep 16, 2010 #6

    gabbagabbahey

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    I'm not here to teach a week of coursework. Read the section in your text that talks about spacetime intervals and then try the problem.
     
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