12. A tungsten filament lightbulb (resistivity at 20°C of 5.6x10-8 2m, temperature coefficient of 0.0045/°C) at 20°C has a resistance of about 9.5 N. a. When you apply 120 V to it, what is the current through it? [12.6 A – this high current is why filament lightbulbs are more likely to break when first turned on.] b. How much power does it use at this temperature? [1516 W – pretty bright] c. Current flowing through the filament heats it quickly, which increases the resistance. A tungsten filament is heated to about 2480 °C. How much power does it use now? [126 W -

12. A tungsten filament lightbulb (resistivity at 20°C of 5.6x10-8 2m, temperature coefficient of 0.0045/°C) at 20°C has a resistance of about 9.5 N. a. When you apply 120 V to it, what is the current through it? [12.6 A – this high current is why filament lightbulbs are more likely to break when first turned on.] b. How much power does it use at this temperature? [1516 W – pretty bright] c. Current flowing through the filament heats it quickly, which increases the resistance. A tungsten filament is heated to about 2480 °C. How much power does it use now? [126 W -

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter17: Current And Resistance

Section: Chapter Questions

Problem 21P

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Similar questions

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