DC Circuits
Kirchoff's Rules ![]()
Not all circuits can be reduced to sets of series and parallel resistors. (Notice that the three circuit diagrams above all describe the same circuit).
How can we handle a circuit like this which is more complex than being a combination of series and parallel pieces?
Assign a current In through each resistor.
At each junction, the sum of the currents in must equal the sum of the currents out; this is just charge conservation.
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Around any circuit loop, apply energy conservation in the form of
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For our example,
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Watch the signs!
With both of Kirchoff's Rules, there will be enough information,
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