When the current in an electrical appliance exceeds its designated safe limit, the fuse in the circuit acts to protect the appliance. Which of the following statements correctly describes how the fuse operates to protect the circuit?
The fuse wire heats up, melts, and breaks the circuit, completely stopping the current.
The fuse wire increases its electrical resistance to reduce the current back to a safe, non-zero level.
An electromagnet inside the fuse pulls a contact switch open, which can then be manually reset.
The fuse wire conducts the excess current away and directs it entirely into the earth wire.
135 exam-style questions on CIE IGCSE Physics Electrical safety, covering Electrical safety. Each one has a worked solution and a mark scheme showing where the marks go.