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Homework Help: Straight Line Motion

  1. Feb 18, 2010 #1
    1. The problem statement, all variables and given/known data
    In 1 km races, runner 1 on track 1 (with time t1 = 147.95 s) appears to be faster than runner 2 on track 2 (t2 = 148.15 s). However, length L2 of track 2 might be slightly greater than length L1 of track 1. How large can L2 - L1 be for us to still conclude that runner 1 is faster?

    2. Relevant equations
    v = L / t

    3. The attempt at a solution
    I got it down to L2t1 - L1t2 < 0, but can't figure out how to get L2 - L1 out. I know I probably have to use the fact that L is approximately 1 km, but I'm not seeing how to do it.
  2. jcsd
  3. Feb 20, 2010 #2


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    Science Advisor
    Homework Helper

    Hi GunnaSix! :smile:

    Why not just put L1 = 1 km?
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