Electrical – How to find open circuit voltage in this circuit


I need to find IR4 along with UR4 using Thévenin's theorem. That means I need to remove resistor R4 and find open circuit voltage. I tried to simplify the circuit by using the fact that on U is formed voltage divider, but I don't know how to proceed next. Could you show me any efficient method how to find Ui?

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Best Answer

First find RTH: Step 1, remove the load: R4 in your case. Step 2, replace the voltage source (U) with short circuit. Step 3, reduce resistors in parallel to one resistor, reduce resistors in series to one resistor; repeat these steps as necessary. You should end up with one resistor.