5D20.20 - Temperature Dependence of Resistance - Iron Wire and Flame
Plug the 6 V battery into the iron wire and burner unit and observe the brightness of the light bulb. Start the burner and as the iron wire gets hot you will see the light bulb dim and go out. Turn off the flame and bulb will again glow visibly as the wire cools.
- Don Rathjen, Paul Doherty, "Sensitive Filament", Square Wheels, 2002, p. 89.
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