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Traffic lights are being converted from incandescent bulbs to LED arrays to save operating and maintenance costs. Typically, each incandescent light uses three 100-W bulbs, one for each color R, Y, G. A competing LED array consists of 61 LEDs with each LED requiring 9 V and drawing 20mA of current. There are three arrays per light—R, Y, G. A small city has 1560 traffic signals. Since one light is always on 2417 , how much can a city save in 1 year if the city buys their electricity at

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ANALYSIS+DESIGN OF LINEAR CIRCUITS(LL)
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- Delmar's Standard Textbook Of ElectricityElectrical EngineeringISBN:9781337900348Author:Stephen L. HermanPublisher:Cengage Learning
