what a Fuse?

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Fuse is a safety device that is installed in an electric circuit. Every circuit needs an electric current to operate. If the circuit or its electricity supply develops a fault, too much current may flow and damage the circuit or cause a fire. A fuse is placed in the electrical supply line to prevent this. The most commonly used type off use is a length of thin wire inside a glass tube between two metal end-caps. When a circuit operates correctly, the fuse allows the current to pass through. But if the current rises, the fuse wire heats up and melts to break the circuit.

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