A small bulb delivers an electrical power of 7.5 W when operated at 125 V. The tungsten filament has a temperature coefficient of resistivity of alpha = 4.5 x 10 ^ (- 3 / ° C) When the filament is hot bright, its temperature is seven times the ambient temperature of a room (20 ° C). What is the resistance of the filament (in ohms) at room temperature? a. 5630 b. 4530 c. 1911 d. 1280

A small bulb delivers an electrical power of 7.5 W when operated at 125 V. The tungsten filament has a temperature coefficient of resistivity of alpha = 4.5 x 10 ^ (- 3 / ° C) When the filament is hot bright, its temperature is seven times the ambient temperature of a room (20 ° C). What is the resistance of the filament (in ohms) at room temperature? a. 5630 b. 4530 c. 1911 d. 1280

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 91CP: A student uses a 100.00-W, 115.00-V radiant heater to heat the student’s dorm room, dining the hours...

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