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Homework Help: Motion in 1D: A Tortoise & A Hare

  1. Feb 10, 2009 #1
    1. The problem statement, all variables and given/known data
    A tortoise can run with a speed of 0.10 m/s, and a hare can run 20 times as fast. In a race, they both start at the same time, but the hare stops to rest for 5.0 minutes. The tortoise wins by a shell (40 cm).
    (a) How long does the race take? (s)
    (b) What is the length of the race? (m)

    2. Relevant equations

    d= distance
    s= speed
    t= time
    subscripts;
    h=hare
    t=tortoise

    dh=sh x th
    dt=st x tt


    3. The attempt at a solution

    i have these two equations:

    dt-0.40=(20)(0.10)(t-300)

    d=0.10t

    how do i set them equal to each other
    or how do i solve them? i have no clue.....
     
  2. jcsd
  3. Feb 11, 2009 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi aznbaby! Welcome to PF! :smile:
    (shouldn't the second equation also be dt?)

    Just put the two d's equal :wink:

    which gives you t = … ? :smile:

    (though personally I'd have defined dh = (20)(0.10)(t-300), and then put dh = dt - 0.40)
     
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