Solution to: Replacement Resistance
The circuit can be redrawn as follows:
The voltage at both ends of the middle resistance is now equal and therefore the circuit consists of two parallel parts, each consisting of two serial resistances.
Conclusion: The replacement resistance Rreplacement is 1, since 1 / Rreplacement = 1 / (1 + 1) + 1 / (1 + 1).
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