1. The problem statement, all variables and given/known data This circuit includes 4 resistors whose value of 3 of them is known and the forth resistor, Rx is unknown. They connected an ammeter A to the circuit and the current through it is 0. 1) Calculate Rx. Is the value of Rx depends on the ammeter resistance A? Explain. 2) Write the name of the circuit 3. The attempt at a solution I seem to be getting way too many unknowns! Rx = unknown I0 unknown I1 = unknown I2 = unknown V = unknown I'm not sure how to derive more equations. Or how to use the ammeter. If I'm told it has 0 current, than it must have 0 voltage, and must have 0/0 resistance! So, how do I even treat it? And why do they mean by the "name" of the circuit? I personally named him Electrobob before I started the exercise and I refuse to change it!