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0.75c+0.75c = 0.96c

  1. Dec 6, 2009 #1


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    a while back I was asking about this, I can't find the thread but I figured I would post this here just incase someone like me can find it searching through google.

    You have to use these special velocity addition formulas.
    like this:
    http://img704.imageshack.us/img704/267/screenshot20091206at124.png [Broken]
    then you find out the 0.75c+0.75c = 0.96c

    c(1.5)/(1+0.3249)=0.96 c
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Dec 7, 2009 #2
    Re: .75c+.75c

    So if one object is approaching me at the speed of 0.75c, and another object is approaching me at the same 0.75c but in direction opposite of the first one, the velocity with which they're closing up on each other is 0.96c?

    I know this has been asked a million times, but I've never paid much attention.
  4. Dec 7, 2009 #3


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    Staff Emeritus
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    Gold Member

    Re: .75c+.75c

    .96c is what observers aboard each vehicle would measure as the speed of the other vehicle
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