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Homework Help: Plane drops packages confounded again!

  1. Sep 5, 2008 #1
    1. The problem statement, all variables and given/known data

    A supply plane needs to drop a package of food to scientists working on a glacier in Greenland. The plane flies 108 m above the glacier at a speed of 175 m/s.

    How far short of the target should it drop the package?

    What speed does the package have when it hits the ground?

    In what direction is the package moving when it hits the ground?
    degrees below the horizontal (or the "x" axis).

    2. Relevant equations
    Vf= V0 +at
    Deltax= V0t+ .5at^2
    Vf^2= V0^2 +2ax

    3. The attempt at a solution
    I can't seem to figure out enough information for this to work. The horizontal acceleration always being zero is halting me from attaining more info. The verticle motion is the same, except with even less. I have only the change in x and the acceleration. I wish to find the time as well, but it seems rather impossible.

  2. jcsd
  3. Sep 5, 2008 #2


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    In these kind of problems, you always consider the horizontal and the vertical problem separately. The general way to handle them is:
    - In the vertical direction, use something like y = h - 1/2 g t^2 to find the total falling time tf
    - In the horizontal direction, the velocity vh is constant, so the horizontal distance travelled is vh * tf.

    For the first question, that approach will work.
  4. Sep 5, 2008 #3
    Gotcha. Figured out what I was doing wrong. Thanks!
  5. Sep 5, 2008 #4


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    Did that also help you answer the other questions?
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