What is the link between the thickness of the wire and the current needed to melt a wire?

Answer 1

Well, I am also doing this same question and its all about resistance.

Resistance is when the electrons flow around a circuit and they collide with ions. These electrons transfer energy to the ions, which consequently get hot and move more so the resistance increases :)

So the thicker the wire is, the less resistance it would have because there are more choices of pathways for the electrons can take without colliding with the ions. Therefore less resistance, more current needed to melt the wire.

So the thicker the wire is, the more current is needed to melt it

Answer 2

The larger the wire the more current it can handle. If the wire is too small for the current flowing through it, it acts more like a resistor in the circuit. The wire heats up in this scenario, can melt the insulation around the wire and cause short circuiting and potentially electrical fires.

Answer 3

Current flowing THROUGH a wire is affected by resistance. Generally a thicker wire will have less resistance than a thinner wire.