(a) Of what substance is the fuse wire made? Why?
(b) Explain why, a copper wire cannot be used as a fuse wire.

(a) The substance used in the making of a fuse wire is tin-plated copper because it has a low melting point. If the current exceeds a safe value, the wire melts and breaks the circuit.

(b) A copper wire cannot be used as a fuse wire because it has a high melting point, and due to this, it will not melt easily in case of a short circuit.