What is the function of a circuit fuse?

A circuit fuse plays a crucial role in electrical systems by serving as a safety device that prevents damage to the circuit from overloads and short circuits. When the current flowing through the circuit exceeds a predetermined limit due to an overload or a fault in the wiring, the fuse contains a metal strip that melts and breaks the circuit. This interruption of the circuit stops the flow of electricity, thereby protecting the wires and devices connected to the circuit from potentially destructive excess current.

In contrast, options that suggest roles such as ensuring maximum voltage or increasing current flow do not accurately describe the purpose of a fuse. A fuse is not responsible for managing voltage levels nor does it assist in enhancing current—its primary objective is to act as a safety mechanism. The option related to measuring electrical output is also inaccurate, as measuring devices like ammeters or voltmeters are used for that purpose, rather than fuses which are purely protective in nature.