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Motion Problem

  1. Jan 29, 2007 #1
    1. The problem statement, all variables and given/known data

    A jet flys at a constant speed of 240 m/s past an antiaircraft missile battery. A time 2.326e+01 s later, an intercepter missile is launched (from rest). The missile has an acceleration of 40 m/s^2.

    How much time (from the instant the missile is launched) does it take the missile to catch up to the jet?

    2. Relevant equations

    3. The attempt at a solution

    I honestly dont even know where to begin. I believe i will at some point have a quadratic formula to work with, is this correct?? I think i need to find where the distances are equal then find the time.
  2. jcsd
  3. Jan 29, 2007 #2
    You don't actually have to find the distance; but for the plane, you should be able to use an equation for distance, in terms of time, and for the missile, you'll also need an equation for distance in terms of time - an equation that includes acceleration. By setting these two equal to each other, you can solve for time, and you're correct, it should be a quadratic equation.

    I think the problem wants you to assume that the jet flies just above the missile battery (not at some high elevation such as 8000 meters).
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