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Homework Help: Homework question on special relativity

  1. Nov 24, 2011 #1
    1. The problem statement, all variables and given/known data

    Samantha, Tom, and Roberta are triplets.

    (i) Samantha is an airline pilot who flies along a straight flight path at 300 ms-1 for 80 hours per month (in her rest frame). How much younger will she be than her brother Tom (who handles baggage at the airport) when she retires after 30 years?

    2. Relevant equations

    Time dilation formula

    3. The attempt at a solution

    Use the time dilation formula t = γt0, where t is the time in the moving frame (that of Tom) and t0 is the time in the rest frame (that of Samantha).

    t0 = (3600*80*12*30) = 103680000 s
    v = 300 ms-1

    Therefore, t = t0 + (51.84 ms), using the binomial expansion in the calculation.

    So, Samantha will be 51.84 ms younger when she retires after thirty years.

    Could you please confirm if I am right?
  2. jcsd
  3. Nov 24, 2011 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Seems like you're off by a few powers of 10. (Unless I messed up the calculation.)

    What did you get for γ-1?
  4. Nov 24, 2011 #3
    I think I have spotted the error. Is your answer in microseconds rather than milliseconds?
  5. Nov 24, 2011 #4
    i.e. 51.84 microseconds.
  6. Nov 25, 2011 #5

    Doc Al

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    Staff: Mentor

    That's it. μs, not ms.
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