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Albert Einstein Theory

  1. Dec 21, 2016 #1
    1. The problem statement, all variables and given/known data
    If someone on a space ship looked at a clock on earth travelling at 99.5% the speed of light what would they notice?
    2. Relevant equations

    3. The attempt at a solution
    Would they notice that time is faster on earth? Is my assumption correct
  2. jcsd
  3. Dec 21, 2016 #2


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    Gold Member

    Your question is rather poorly formed. Assuming that you meant that there is a spaceship approaching Earth at 99.5% of c, then what they would see with their eyes (via telescopes) is that clocks on Earth would be ticking faster than the ones on the ship.
  4. Dec 21, 2016 #3
    yes that's exactly what I meant. Sorry for my poor wording.!
  5. Dec 22, 2016 #4
    What assumption?

    Are you familiar with the Lorentz Transformation?
  6. Dec 22, 2016 #5


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    If there is a spacecraft receding from earth at 99.5% of c then they would see the clocks on earth ticking more slowly than the ones on the ship.

    But "how much faster?" and "how much slower?". That's where things start to get interesting.
  7. Dec 22, 2016 #6


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    @Veronica_Oles I think we may be confusing you because of language differences but when I went to look at your profile to confirm that you are not native to the US I was denied access. Really? You join a forum to ask questions but you don't want us to know about you?

    That's your right of course but it seems self-defeating to me.
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