complex conjugate ??

Discussion in 'Homework Help' started by marty4, Sep 6, 2012.

  1. marty4

    Thread Starter New Member

    Aug 27, 2012
    3
    0
    Hi Guys,

    I have a question thats bugging me, if you can help.

    I need to calculate Is when I1 = 4 + j10 Z1= 9+J10 Z2=2 + j6.

    Is= I1x Z1/Z1 + Z2.

    Is this just multiplying by the complex conjugate?

    Would I just do (9 +j10)
    (9 +j10 + 2 + j6)

    = (9 +j10) x (11 - j16)
    (11 +j16) (11 - j16

    Then multiply the answer by I1 which would be 4?

    Thanks Guys.
     
  2. nobody0608

    New Member

    Aug 4, 2012
    28
    2
    Hello,

    Let me check first whether I get what you means. Is the equation below same with yours?
    [​IMG]

    If yes then your steps are correct, but the final answer is not equal to 4.
     
  3. marty4

    Thread Starter New Member

    Aug 27, 2012
    3
    0
    Hi,

    Yes I meant, do the( Z1/Z1 + Z2 ) equation first then multiply by I1 (4)?

    Cheers.
     
  4. marty4

    Thread Starter New Member

    Aug 27, 2012
    3
    0
    It's ok I got it..

    Cheers....
     
  5. WBahn

    Moderator

    Mar 31, 2012
    17,757
    4,800
    This equation has units problems. Z1/Z1 is simply 1 (no units), so (Z1/Z1 + Z2) is (1 + Z2) and you can't add something that has no units to something that has units of impedance (i.e., ohms).

    Normally, if you have a Z1 and then talk about I1, it means that I1 is the current through Z1. But if I use that convention, then I have no idea what you are trying to do.

    It would really, really help if you provided a circuit, or at least a description of a circuit, so that we didn't have to try to read your mind.
     
Loading...