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Homework Help: Distance and time question

  1. Sep 13, 2007 #1
    1. The problem statement, all variables and given/known data

    a pack of hounds running at 23.0m/s is 66.0m behind a mechanical rabbit, itself sailing along at 6.0m/s.

    2. Relevant equationsa) how long will it take before the rabbit is caught? b) how far will it travel before being over taken?

    3. The attempt at a solution
    I can't even figure out where to start. I tried Vit + 1/2 At2-x . I just can't figure how to set this up.
  2. jcsd
  3. Sep 13, 2007 #2

    Doc Al

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    Staff: Mentor

    Both hounds and rabbit are moving at constant speed so there's no acceleration to worry about. The key formula is X = Xi + Vt.

    Write expressions (using the formula above) for the position of hounds and rabbit, then solve them together to find the time.
  4. Sep 13, 2007 #3


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    Homework Helper
    Gold Member

    OK. So you have two different systems here, the pack of dogs and the rabbit. They are both moving at different rates and you want to know when they are at the same place.

    Can you give me an equation that describes the motion of the rabbit? the pack? If you can you would have two equations both in terms of position and time. Then you have two equations and two unknowns, you should be able to solve for both.

    EDIT: You beat me to it Doc Al!
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