State Kirchhoff's Current Law (KCL).

"At any node (or junction) in an electrical circuit, the sum of the currents entering the node is equal to the sum of the currents leaving the node."

In other words, the total current flowing into a node is equal to the total current flowing out of that node. This law is based on the principle of conservation of electric charge. Since charge cannot be created or destroyed, any charge entering a node must also leave the node through other paths within the circuit.

Mathematically, KCL can be expressed as:

Σ I_in = Σ I_out

Where:

Σ I_in is the algebraic sum of all currents entering the node.

Σ I_out is the algebraic sum of all currents leaving the node.

KCL is a crucial tool for analyzing and solving electrical circuits, especially in cases where multiple branches and currents intersect at a single node. By applying KCL to various nodes in a circuit, one can determine the current distribution throughout the network and understand how different components interact with each other.