Been racking my brains over this one and I'm stuck maybe someone here can help me. I'm doing physics through distance education at high school and its very difficult.
"In house fires the wiring is often cited as the cause of the fire. Often this wiring is partially corroded through or cracked. Explain why this may be a contributing factor in causing the fire by referring to what you have learned about resistance."
The Attempt at a Solution
I honestly have no idea at all how the crack or corrosion could cause a change in resistance and lead to a fire. I have learned that the following factors influence resistance:
1 - length
2 - type of material
3 - cross sectional area
4 - temperature
As well as this I'm aware of Ohm's law...
I'm thinking it may have something to do with the temperature but I'm really just pulling ideas from nowhere.
Any help would be very very much appreciated.