AP Physics C: Electricity and Magnetism / Unit 11: Electric Circuits
11.7 Kirchhoff's Junction Rule
Notes
$\displaystyle \sum I_{in}=\sum I_{out}$ at every junction.
Practice
4 A and 3 A enter a junction; one wire leaves. Its current:
Sum.
The junction rule expresses conservation of:
Charge doesn't accumulate.
If a solved current comes out negative, it means:
Just the direction.
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