Code Number: 5D20.20

Demo Title: Temperature Dependence of Resistance - Iron Wire and Flame

Condition: Excellent

Principle: Temperature vs. Resistance

Area of Study: Electricity & Magnetism

Equipment:

Unit with iron wire wrapped around the spacers with the burner underneath and a light bulb, 6V battery, grill lighter.

Procedure:

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.

References:

Don Rathjen, Paul Doherty, "Sensitive Filament", Square Wheels, 2002, p. 89.

5D20.20 - Temperature Dependence of Resistance - Iron Wire and Flame

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