General Knowledge - Basic General Knowledge - Discussion

A fuse wire should always have a high resistance and low melting point.

High resistance to heat up soon and low melying point to melt away due to the heat produced by high resistance so that the circuit is not damaged.

A fusible alloy is a metal alloy capable of being easily fused, i.e. easily meltable, at relatively low temperatures. Fusible alloys are commonly, not necessarily, eutectic alloys.

Sometimes the term "fusible alloy" is used to describe alloys with a melting point below 150 degree C (302 degree F). Fusible alloys in this sense are used for solder.

So both A and B are right

Basic idea is to protect household devices. So that only that fuse will spoil due to high current rest house devices get protected. Because fuse cost is less. It can be replaced as it's cost is low compared to costly house hold circuit devices.

The fuse wire must be of low melting point. When excess current is flowed the fuse wire melt up and electrical appliances are saved.

If the melting point of fuse wire will be more, then it will take more time to disconnect the supply system at the time of fault occurred and the electronic components will be get damaged.

So melting point must be low for fuse wire.

The melting point of a solid is the temperature at which the vapor pressure of the solid and the liquid are equal. At the melting point the solid and liquid phase exist in equilibrium. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of some substances to supercool, the freezing point is not considered to be a characteristic property of a substance. When the "characteristic freezing point" of a substance is determined, in fact the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice", that is, the melting point.

Low melting point is the answer. Because fuse wire should be broken when an excess current flows through it. (according to H=I^2*R*T ).

Yes low melting point is the answer so as to prevent a short circuit from materializing because if a high current passes through it, it would melt and thus break the circuit.

A fuse wire must have high resistance and low melting point.