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Homework Help: Another 2 dimensional problem

  1. Jun 2, 2006 #1
    another 2 dimensional problem :(

    The best leaper in the animal kingdom is the puma, which can jump to a height of 11.5ft (3.51m) when leaving the ground at an angle of 43 degress. With what speed, must the animal leave the ground to reach that height?

    at first i thought i could find the time it took for the puma to get to it's maximum height by setting V=0 but i dont that's right...

    i tried using the equation

    change in y=(sin43)Vot-.5g(t^2)

    with change in y = 3.51 m


    but i dont know how to solve for t or Vo

    this question would be so much easier if the question gave the horizontal distance but it doesnt..so what do i do?
     
  2. jcsd
  3. Jun 2, 2006 #2

    Hootenanny

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    You need a kinematic equation with inital velocity, final velocity, acceleration and displacement. Can you think of one?

    HINT: You know the final velocity

    ~H
     
  4. Jun 2, 2006 #3
    is it V^2=Vyo^2 + 2ay

    a= -9.8
    im assuming final velocity= 0 b/c that's what v is going to = at its max height

    thank you...i ended up with the right answer
     
  5. Jun 2, 2006 #4

    Hootenanny

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    Spot on. No problem :smile:

    ~H
     
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