[Physics] Current flow in a Bridged T filter

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Currently Learning about circuits and have been given the following question.

"The circuit below is a bridged T filter. Label all of the current directions and use complex impedance analysis to write down the simultaneous equations that are needed to determine the transfer function for such a filter". $C$ is a capacitor and $R$ is a resistor.

I don't want an answer to the question as I want to do it myself, I only want an answer and explanation to how the current flows through the circuit and what the output voltage is. My only guess is that the current could either flow through C1 and R1 or through R2, C2 and R1. I am really struggling to understand circuit diagrams like this and any help would be fantastic. enter image description here

Best Answer

Have you learnt the Kirchoff current and voltage laws? Personally, I would define three loop currents, one flowing through C1, R1 from the input, one through C2 R1 from the output in the opposite direction and a loop current throuhg R2, C1, C2 as I've shown. Now write down the sum of voltages around the loops, using the complex impedance to relate the voltage across each element to the loop currents. For example, the voltage across $C_1$ will be $-\frac{i}{\omega\,C_1}\,(I_{in}-I_m)$. You'll get three equations from equating the sum of voltages around loops to nought which will define the loop currents.

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