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Homework Help: Complex potential

  1. Mar 11, 2007 #1
    1. The problem statement, all variables and given/known data
    Iv been given the complex potential equation ..iv been trying to split it into real and imaginary parts so i can find the streamfunction and potential for it...however the ln is making it difficult




    2. Relevant equations



    3. The attempt at a solution

    iv tried taking out a factor of two from 2i +4 and raising it to the ln part....so i get ln (x+iy)^2...i expanded that but i still got imaginary parts inside

    so i was wondering if anyone knows any other ways to split the equation into imaginary parts and real parts
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     

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    Last edited: Mar 11, 2007
  2. jcsd
  3. Mar 11, 2007 #2

    Dick

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    Homework Helper

    You'll want to express x+iy in the form r*exp(i*theta) and then think about evaluating the log.
     
  4. Mar 11, 2007 #3
    Thanks that makes sense..i got it in my notes but just dont when to apply it
     
  5. Mar 11, 2007 #4
    streamline question

    i was wondering if my u is right, as my problem deals with two dimensional inviscid steady potential flow and there are are various ways to find u = u(r,theta)er + v(r,theta)etheta

    u= (-2/r)*er +(2/r)*etheta

    and if so i was wondering how to sketch streamlines...using the previous question posted above i found that the speed of the particle was
    u= (-2/r)*er +(2/r)*etheta
     
    Last edited: Mar 11, 2007
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