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Homework Help: Speed of ship as fraction of speed of light

  1. Sep 23, 2008 #1
    1. The problem statement, all variables and given/known data

    Jane gets in her spaceship on her twenty-fifth birthday and flies to the star Vega at a constant velocity v. She is just turning age 31 when she reaches the Vega system.

    What is the speed of her ship, as a fraction of the speed of light c?

    2. Relevant equations

    3. The attempt at a solution

    I have attempted this 7 times. I have 3 chances left. I found out that the distance to Vega to be 25.3 Light years and i converted that to meters and then i converted 6 years to seconds and I still could not get the right answer. I have to express the answer as a fraction of the speed of light, but i continue to get a value that is 4x the speed of light. Any ideas?

    Thanks in advance
  2. jcsd
  3. Sep 23, 2008 #2


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    Science Advisor
    Homework Helper

    Yes, look up time dilation. 4x speed of light is not an option. This course does have some content about special relativity, right? The rate of passage of time on the ship is not the same as in the rest frame of earth and Vega.
  4. Sep 24, 2008 #3
    i had originally did the space time interval but now that i looked back at it i did have a miscalculation. Thanks for the help! got the right answer.
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