What defines a short circuit in an electrical system?

A short circuit is defined by a flow of current along an unintended path. In an electrical system, current is meant to travel through designated conductors such as wires and components like resistors or loads. When a short circuit occurs, the current bypasses these components and flows directly through a low-resistance path. This unintended path can lead to excessive current flow, which generates heat and can potentially cause damage to the electrical system, overheating, or even fires.

The other options do not accurately describe a short circuit. A sudden increase in voltage relates more to voltage surges, which can occur due to various reasons but are not indicative of a short circuit. A component that generates heat could refer to a resistor or any device engaged in converting electrical energy to heat, but it does not define a short circuit, which is specifically about the flow of current rather than any particular component. A complete pathway for current flow describes a normal circuit where current travels through all designated components correctly; however, this does not capture the essence of a short circuit, where the pathway bypasses intended routes.