Define short circuit.

A short circuit is defined as an unintended path of low resistance that allows excess current to flow. In electrical systems, when a short circuit occurs, it can bypass normal current flow and create a path that has much lower resistance than the intended circuit paths. This results in a surge of current that can lead to overheating, equipment damage, and even fires if protective devices like fuses or circuit breakers do not interrupt the flow.

Understanding this definition is crucial because it highlights the risks associated with short circuits, which include not only damage to circuits but also safety hazards in residential and commercial settings. The other choices describe different concepts: excessive resistance does not relate to short circuits as it attributes a different behavior to a circuit, while a temporary interruption of a connection and multiple branches in a circuit refer to different circuit configurations rather than low-resistance pathways.