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Homework Help: Find the time of a race

  1. Oct 9, 2015 #1
    1. The problem statement, all variables and given/known data
    A tortoise can run with a speed of 10.0 cm/s, and a hare can run exactly 10 times as fast. In a race, they both start at the same time, but the hare stops to rest for 3.00 min. The tortoise wins by 10 cm.

    (a) How long does the race take?

    (b) What is the length of the race?

    3. The attempt at a solution

    I know how to solve it

    However in the solve sheet it says:


    Where does the 0,2 come from? isnt it 0,1 meters when they cross the line. OR is it something about "the second before"
  2. jcsd
  3. Oct 9, 2015 #2


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    Homework Helper

    The right hand side says how far the hare ran in the total time of the race, which is t_tortoise. It should be assume that if the tortoise won by 10cm, that the hare completed all but 10cm of the race in that time. I am inclined to agree with your interpretation.
  4. Oct 9, 2015 #3


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    2017 Award

    Staff: Mentor

    That should be -0.1.
    Units are missing.
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