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Homework Help: Acceleration problem

  1. Sep 21, 2005 #1
    A person is on the roof of a building, 46.0 m above the ground. His teacher, who is 1.80 meters tall, is walking toward the building at a constant speed of 1.20 m/s. If the person wishes to drop the egg on his teacher's head, where should the teacher be when the person releases the egg?

    So I know that I need to set two equations equal to each other to get the position the teacher needs to be for the egg to drop on him. So should I use [itex] x = v_{y}_{0}t + \frac{1}{2} a_{x}t^{2} [/itex] for the egg, and [itex] x = x_{0} + v_{x}_{0}t + \frac{1}{2} a_{x}t^{2} [/itex]?

    Thanks
     
  2. jcsd
  3. Sep 21, 2005 #2

    Fermat

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    How far does the egg have to fall before impacting on the head of the 1.8 m tall teacher ?
    How long will it take for the egg to fall this distance ?
    How far can teacher walk in this time ?
     
  4. Sep 21, 2005 #3
    Thanks. I got the answer.

    1. [itex] 46 - 1.8 = 44.2 m [/itex]
    2. [itex] 44.2 = \frac{1}{2} (9.8) t^{2}, t = 3 [/itex]
    3. [itex] x = 0 + 1.20(3) = 3.6 m [/itex]
     
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