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Homework Help: Tricky Kinematics 2 Dimension

  1. Sep 24, 2008 #1
    hi, im new to this forum and i have been having great difficulties with this question...

    1. The problem statement, all variables and given/known data

    An airplane with a speed of 81.6 m/s is climbing upward at an angle of 44.7 ° with respect to the horizontal. When the plane's altitude is 944 m, the pilot releases a package. 1) Calculate the distance along the ground, measured from a point directly beneath the point of release, to where the package hits the earth. 2) Relative to the ground, determine the angle of the velocity vector of the package just before impact.

    2. Relevant equations
    any possible kinematics equation

    Anyone have any ideas, it wud extremely helpful

  2. jcsd
  3. Sep 24, 2008 #2


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    Hi there guty and welcome to PF! You should think about what the relevant equations are out of all the 'possible kinematic equations'. Are you familiar with the projectile motion 2D equations?
  4. Sep 24, 2008 #3
    yes i think so

    the 4 equations are

  5. Sep 25, 2008 #4


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    Sorry to leave you hanging there. Yes, those are the general motion equations for motion. For projectile motion problems, such as the one you are working on, there is motion in 2D, the x and y direction. Once the package is released from the plane, the only force acting on the package is the gravity force downward , with an acceleration of g vertically downward. There is no force in the x direction, thus there is no acceleration in the x direction. So in the y direction, where ay =-g, you have v2y = v1y -gt, etc., and in the x direction, where ax =0, you have v2x = v1x, x = v1t, etc. So you have to find v1x and v1y from the given value of v1, then use these equations properly to get your answer. You might want to google on 'projectile motion' for sample problems.
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