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Homework Help: Does this has anything to do with relativity?

  1. Jan 4, 2010 #1
    1. The problem statement, all variables and given/known data
    The Starship Enterprise, apparently escaping from the clutches of Cthulhu (the image was not altered, this is how it was given!) is flying to the moon at a velocity of 0.7c.
    How long will it take (in seconds) for it to get to the moon, as observed from the Earth's frame of reference.
    D from Earth to the Moon is 384,000 Km.
    At t=0 the ship is over the earth

    http://img229.imageshack.us/img229/4001/spaceshiptothemoon.png [Broken]

    2. Relevant equations


    3. The attempt at a solution

    Am I wrong to assume this has nothing to do with relativistic time dilation or shortening of distances and what-not?
    This seems to be a straightforward calculation.
    So is this right:
    384,000 Km = 3.84*10^8 m
    c = 3*10^8 m/s
    [tex]\frac{3.84*10^8}{0.7*3*10^8}[/tex] = 1.828571428 seconds.

    I got this in a relativity assignment so I'm suspicious of this solution.
    If I missed something please let me know.

    *can't edit the title, obviously should be "have"...
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jan 4, 2010 #2


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    In the Earth's reference frame it's just the distance and time.
    From the point of view of the crew time would be different.
  4. Jan 4, 2010 #3
    Thank You!
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