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Basic Theory

Kirchhoff's Laws

Kirchhoff's Laws Kirchhoff's Current Law (KCL) Definition At any node, the sum of currents entering the node equals the sum of currents leaving the node. Formul…

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Kirchhoff’s lawsKCLKVLCircuit analysis

Kirchhoff's Laws

Kirchhoff's Current Law (KCL)

Definition

At any node, the sum of currents entering the node equals the sum of currents leaving the node.

Formula

ΣI_in = ΣI_out

Kirchhoff's Voltage Law (KVL)

Definition

In any closed loop, the algebraic sum of all voltages equals zero.

Formula

ΣV = 0

Application Examples

KCL Application:

Node A: I1 + I2 = I3

KVL Application:

Loop: V - I×R1 - I×R2 = 0