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Homework Help: Maths or physics Interception question

  1. Aug 23, 2004 #1
    Two airports (A and B) are 200nm apart. Aircraft 1 leaves airport A and
    flies to B at 100kts. Aircraft 2 leaves airport B and flies to A at 200kts.
    Both aircraft leave at the same time, where relative to airport A will they
    pass each other?

    nm=nautical miles
  2. jcsd
  3. Aug 24, 2004 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Here's one way to solve this. Call the time at which they pass each other t. During that time, each flies a certain distance D = V t. So aircraft 1 travels a distance [itex]D_1 = V_1 t[/itex] and aircraft 2 travels a distance [itex]D_2 = V_2 t[/itex]. But the total distance traveled by both aircraft must equal the distance between A and B (200 nm). I'll leave the next step to you: set up the equation and solve for t, then plug t in to solve for [itex]D_1[/itex].

    Once you understand what's happening, you can practically do this problem in your head. Realize that the distance each aircraft travels is proportional to its speed. Aircraft 1 travels half as fast as aircraft 2, so it travels half the distance of aircraft 2. If aircraft 1 travels D, aircraft 2 travels 2D. The total is 3D = 200 nm. Solve for D.
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