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Homework Help: Help with velocity

  1. May 10, 2009 #1
    1. The problem statement, all variables and given/known data

    Larry leaves home at 11:08 and runs at a constant speed to the lamppost. He reaches the lamppost at 11:17, immediately turns, and runs to the tree. Larry arrives at the tree at 11:22. What is Larry's average velocity during his trip from home to the lamppost, if the lamppost is 371.0 m west of home, and the tree is 630.0 m east of home?

    2. Relevant equations


    3. The attempt at a solution

    This is what i've done:
    d=371 m
    t = (9*60) = 540 s

    =0.687 m/s

    I'm just wondering what I am doing wrong can someone please help me
  2. jcsd
  3. May 10, 2009 #2


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    Science Advisor
    Homework Helper

    I am wondering what you are doing wrong as well. Why do you think it is wrong? Because I think you did the calculation correctly.
  4. May 10, 2009 #3


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    Homework Helper
    Gold Member

    Is the positive direction of the x-axis pointing east or west? If it's pointing east then you're missing a minus sign.
  5. May 10, 2009 #4
    I strongly suspect that the question meant to ask for the average
    velocity from home to the tree.
  6. May 11, 2009 #5
    Thanks and I was missing the a negative
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