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Homework Help: Plane speed vector problem

  1. Sep 18, 2009 #1
    1. The problem statement, all variables and given/known data
    After flying for 18 min in a wind blowing 49 km/h at an angle of 22° south of east, an airplane pilot is over a town that is 51 km due north of the starting point. What is the speed of the airplane relative to the air, in km/h?

    2. Relevant equations

    all i know to do here is to use the pythagorean theorem and maybe the law of sines to figure out the vectors

    3. The attempt at a solution

    i tried a couple of ways with different triangles but i only have 3 tries left and i seem to be floundering around in the dark on this one!
  2. jcsd
  3. Sep 18, 2009 #2


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    Show us what you tried, then we will be able to correct and explain where you went wrong.
  4. Sep 18, 2009 #3
    i honestly don't even know how to draw the diagram :/ i don't know where to put the starting point of the plane relative to the wind vector or what role the 51 km plays.. the wording is just confusing me
  5. Sep 18, 2009 #4
    Alright, you know that the pilot has traveled 51 km in 18 minutes. You can use that information to find the pilot's velocity after wind resistance.

    Wind is blowing at 49 km/h at an angle of 22 degrees south of east; find component vectors. You can then use the components to find the velocity before wind resistance. I think that's what's being asked.
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