Resistance and Heat: The Truth about Wire Resistance in Circuits

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The discussion confirms that for most materials, particularly metals, increased temperature leads to greater electrical resistance in wires. However, this relationship does not hold true for semiconductors or insulators, which are not typically used as conductors in circuits. The heating power in a wire is proportional to the square of the current multiplied by the resistance (I-squared R). Therefore, it can be stated that as the wire heats up, the current may also increase. Understanding these principles is crucial for circuit design and analysis.
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is this statement true:
the hotter the wire the greater the resistance (when relating to circuits)
 
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For most materials yes.
 
For most materials yes.
It would e.g. be correct for metals; but not neccesarily for a semiconductor or an insulator.
Although you wouldn't normally use these as conductors in a circuit.
 
Note that the heating power varies as I-squared R, so I would first say "the hotter the wire, the greater the current".
Bob S
 

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