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Homework Help: Average velocity

  1. Jan 11, 2009 #1
    1. The problem statement, all variables and given/known data

    A construction worker drops a bolt while working on a high-rise building 320m above the ground. After t seconds, the bolt has fallen a distance of s metres, where s(t) = 320-5t^2, 0 <= t <=8

    Find the average velocity for the interval 3<=y<=8

    2. Relevant equations



    3. The attempt at a solution

    I used the formulas [tex]\Delta[/tex]s / [tex]\Delta[/tex]t
    which then =
    s(8) - s(3) / (8-3)

    ~
    ~
    =55

    Is this right?
     
  2. jcsd
  3. Jan 11, 2009 #2
    The magnitude is correct but I think you want to keep the negative sign to indicate direction.
     
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