Simplify the following circuit (all impedances)

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The discussion revolves around calculating the equivalent impedance between terminals A and B in a circuit with given impedances. The user expresses frustration over the complexity of the problem and considers whether a Y to Delta transformation is necessary. Another participant suggests a simpler approach, indicating that Z1 and Z4 are in parallel, followed by a series connection with Z3, and then in parallel with Z1. The user acknowledges the advice and realizes they were overcomplicating the problem. Simplifying circuit analysis can often be achieved by reevaluating the configuration rather than resorting to transformations.
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Homework Statement


Calculate the equivalent impedance about terminals A and B.
[PLAIN]http://img218.imageshack.us/img218/9335/circuits827.png

Z1 = -j2 ohms
Z2 = 1 ohm
Z3 = j2 ohms
Z4 = 2 ohms

Homework Equations


Adding parallel: Zeq = z1*z2/z1+z2
Adding in series Zeq = z1+z2

The Attempt at a Solution


I honestly have been staring at this problem for hours and cannot figure it out. I'm beginning to wonder if you have to perform a Y to Delta transformation about Z1, Z3, and Z4. Without doing that I cannot see how to simplify this problem. Is there another way? Or, is that the only way to solve it by doing a Y to Delta transformation about Z1, Z3, and Z4.

Help / advice much appreciated in advance.
 
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dphysics said:

Homework Statement


Calculate the equivalent impedance about terminals A and B.
[PLAIN]http://img218.imageshack.us/img218/9335/circuits827.png

Z1 = -j2 ohms
Z2 = 1 ohm
Z3 = j2 ohms
Z4 = 2 ohms

Homework Equations


Adding parallel: Zeq = z1*z2/z1+z2
Adding in series Zeq = z1+z2

The Attempt at a Solution


I honestly have been staring at this problem for hours and cannot figure it out. I'm beginning to wonder if you have to perform a Y to Delta transformation about Z1, Z3, and Z4. Without doing that I cannot see how to simplify this problem. Is there another way? Or, is that the only way to solve it by doing a Y to Delta transformation about Z1, Z3, and Z4.

Help / advice much appreciated in advance.

You are working way to hard.
Z1 & Z4 are in parallel, then in series with Z3, and that result is in parallel with z1.

Just draw the circuit with node A at the top and Node B at the bottom.
 
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Thank you, haha yes I was over analyzing it way too much, I missed that.

Thanks again!
 
Drawing circuits in a 'non-standard' organization is a favorite way to confuse.

You should see what you can do to a bridge circuit to make the arms look out of balance.
 
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