(1) An incandescent light bulb produces 5.85 Joules of light energy each second. This bulb is 7.80% efficient, meaning that only 7.80% the total energy it consumes becomes light and the rest becomes waste heat. A 12.0 W fluorescent bulb is designed to produce the same illumination (in Joules of light energy per second) as the incandescent bulb. A large building uses 17,530 light bulbs. At a cost of 8.56€/kW-hr for electricity, how much money will the owners of the building save each year if they use fluorescent bulbs instead of incandescent bulbs? Express your answer in dollars. [answer: about $828,000]

(1) An incandescent light bulb produces 5.85 Joules of light energy each second. This bulb is 7.80% efficient, meaning that only 7.80% the total energy it consumes becomes light and the rest becomes waste heat. A 12.0 W fluorescent bulb is designed to produce the same illumination (in Joules of light energy per second) as the incandescent bulb. A large building uses 17,530 light bulbs. At a cost of 8.56€/kW-hr for electricity, how much money will the owners of the building save each year if they use fluorescent bulbs instead of incandescent bulbs? Express your answer in dollars. [answer: about $828,000]

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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