Physics Laws & Theorems
Intermediate

Kirchhoff's Current Law

Current into a junction equals current out of it (charge conservation).

Formula

∑Iin=∑Iout\sum I_{in} = \sum I_{out}

Variables

ICurrents at a node

Example

If 3 A and 2 A flow into a junction, exactly 5 A must flow out.

Did You Know?

Kirchhoff's current law is simply conservation of charge — what flows into a junction must flow out.

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