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Clock of observers

  1. Dec 1, 2013 #1
    We have three observers. The A is in earth,B is into a car that runs with big speed,C is out of galaxy.

    All observesr see that their clock runs normal. A will see that clock of B run slower,and B will see the same for A.

    1)
    Logically, C will see A's and B's clock run slower from his clock,but which clock will run slower? A's or B's (I think A's,because has more speed,I am right?)

    2)
    And from the opposite,who from both(A,B) will see C's clock run slower?(I think again A,due of speed).

    I am correct to 1) and 2)


    Thanks!!!
     
  2. jcsd
  3. Dec 1, 2013 #2

    Mentz114

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    Gold Member

    What do you mean by 'see' in this

    If you mean 'by visual contact', then clocks moving away appear slower and approaching clocks appear faster.
     
  4. Dec 1, 2013 #3
    That for observer A,clock of B run slower,and for B,clock of A run slower from his clock.
     
  5. Dec 1, 2013 #4

    Mentz114

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    Gold Member

    Sure, but this is not a directly observable physical effect. It appears when either time is converted from its rest frame coordinates to the moving frame coordinates.
     
  6. Dec 1, 2013 #5

    Nugatory

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    Staff: Mentor

    You still have to specify C's velocity relative to the other two before we can answer the question. Just because he's a looooong ways away doesn't mean he cannot be at rest relative to one, the other, or neither.
    (In special relativity, that is. In the general relativity case, we have to be a lot more careful about specifying C's state of motion).

    You may be on your way to (re)discovering the "Andromeda paradox".
     
  7. Dec 1, 2013 #6
    C is standing about A and B.
     
  8. Dec 1, 2013 #7

    Dale

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    What does that mean?
     
  9. Dec 1, 2013 #8

    Nugatory

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    Staff: Mentor

    C cannot be at rest relative to both A and B. They're moving relative to one another, so anything at rest relative to one is moving relative to the other.
     
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