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Homework Help: Finding sum of phasors when real components cancel out

  1. Feb 6, 2010 #1
    1. The problem statement, all variables and given/known data

    I'm working on a problem where I have to add two phasors together. The problem is, the real parts cancel out and I can't figure out how to express the phase because arctan(y / 0) isn't defined.

    2. Relevant equations

    x1 = 10<45 degrees

    x2 = 10<135 degrees

    x1 + x2 = ?


    3. The attempt at a solution

    x1 in rectangular form = 7.07 + j7.07

    x2 in rectangular form = -7.07 + j7.07

    x3 = x1 + x2 = 0 + j14.14

    x3 magnitude = 14.14

    x3 phase = arctan( 14.14 / 0 )?
     
  2. jcsd
  3. Feb 6, 2010 #2

    rock.freak667

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    Homework Helper


    if x3=14.14j, then it is purely imaginary and thus the vector is parallel to the imaginary plane. So the angle it makes with the real plane is just 90°.
     
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