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I need help understanding this stuff

  1. Apr 26, 2009 #1

    if somethings moving 80% the speed of light then itll age 1/5th as fast relative to you, moving 0.0000% the speed of light right
  2. jcsd
  3. Apr 26, 2009 #2


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    What, exactly is your question? No, if something is moving at 80% the speed of light, it will age at 3/5 your rate, not 1/5: if v= 0.8 c then t'= t sqrt(1- (.8c)^2/c^2)= t sqrt(1- .64)= t sqrt(.36)= t(.6)= (3/5)t.
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