Question

Fuse wire is made up of an alloy of ____ which has high resistance and ____(high/low) melting point.

Answer 1

Fuse is a sacrificial device (a device which is especially designed to be failed at the time of any incident which causes defect or danger to the whole system). When excess current flows through the wire , it breaks down to protect the whole system from getting defected.

Complete step by step answer
When the overflow of current happens in the circuit , excess heat gets developed which leads to disturb the whole system(as per the joule’s effect). This can be a concern as per the security of a system at domestic/industrial level is concerned . It might cause short circuit, mismatch load or device failure.
$H = {I^2}RT$
Where
$H$ is the amount of heat produced
$I$ is the current flowing
$R$ is the resistance offered
$T$ is the time parameter.
The internal wire of fuse (fuse wire) is made up of $Tin$ ($Sn$ ) and $Lead$ ($Pb$ ) of concentration $(37 - 38)\%$ and $(62 - 63)\%$ respectively . since the melting point of this alloy is approximately equal to $180^\circ c$ . This eases the breakdown of circuit owing to the less resistive nature and low melting point.

Note: Fuses are the most crucial and important appliances when it comes to the safety of an electrical system. When we use any alternative material for fuse wire which is less resistive and has a higher melting point then the circuit will not break and the current overflow will cause the appliances/system to get destroyed .