Define Kirchhoff's Voltage Law.

Kirchhoff's Voltage Law (KVL) states that the sum of the electrical potential differences (voltages) around any closed circuit loop must equal zero. This is based on the principle of conservation of energy, implying that any energy supplied by sources in the circuit (like batteries) must be equal to the energy used by components in the circuit (like resistors and capacitors). As you traverse around the loop, the voltages rise (when moving from negative to positive terminal of a power source) and fall (when passing through resistive components), and these changes eventually cancel each other out, resulting in a total of zero volts.

This law is fundamental in circuit analysis as it helps to ensure all energy supplied is accounted for by the energy consumed within closed loops. Understanding KVL is particularly critical when calculating voltages and analyzing the behavior of circuits with multiple components.

The other options refer to different principles or laws in electrical engineering and circuit theory but do not accurately describe Kirchhoff's Voltage Law. For example, one option addresses current at junctions, which relates to Kirchhoff's Current Law instead.