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Speed of light limit

  1. Jan 27, 2012 #1
    If earth is here 0 and I go at 90% the speed of light in that direction <--in my space ship and my friend is going a 90% the speed of light in that direction --> in is space ship so it look like this. 90% <-- 0 --> 90% relative to people on earth we each go at 90% the speed of light in oposite direction, how come relative to my friend I would not be going at 180% the speed of light ? and if so what would be my speed relative to my friend if not 180% ?

    From the point of view people on earth it certainly seem to me that they would see us distance each other at faster than light speed... !?
     
  2. jcsd
  3. Jan 27, 2012 #2

    Matterwave

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    From the Earth's point of view, the distance between you two is increasing at 1.8c. From your point of view, and from your friend's point of view, the distance between you two is increasing at only .9945c.

    See: http://en.wikipedia.org/wiki/Velocity_addition_formula
     
  4. Jan 27, 2012 #3

    ghwellsjr

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