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Homework Help: Graphing a vector with component angles?

  1. Jan 23, 2010 #1
    At the end of a problem (I'm sure I did all the math correctly, that's not an issue) I'm supposed to graph the corresponding resultant vector. However, along with the magnitude of the vector, the angles given are in component form: θx, θy, θz. I've never encountered this before, and although it seems like it's probably easy, I have no idea how to graph such a vector. Can anyone explain how, or is there anything anyone knows of that I can use a reference?
     
  2. jcsd
  3. Jan 23, 2010 #2

    rock.freak667

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    Homework Helper

    Say your vector is R, with components as such <Rx,Ry,Rz>. To get the angle R makes with the x-axis, you'd dot product R with <1,0,0> (unit vector in direction of the x-axis).

    This gives
    <Rx,Ry,Rz>.<1,0,0>=|R|(1)cosθx

    Or simply Rx=|R|cosθx

    Do a similar exercise with the unit vectors in the direction of the y and z axes to get the components Ry and Rz
     
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