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Unformatted text preview: factors affecting the number of lamps required Fluorescent light is produced by _____. Correct B ) converting UV to visible light Fluorescent light is produced by converting UV to visible light Heather is a smart person who wants to save energy and money. So, she has replaced the 120 Watt incandescent light bulb in her house with a 28 Watt CFL bulb. The expected life of incandescent and CFL bulbs is 800 h and 8000 hours respectively. The purchase price of an incandescent bulb is $0.67 and for the CFL it is $5.71. The cost of electricity is 7 cents per kWh. What is her total savings over the life of the CFL bulb? Correct C ) 52.51 CFL energy cost for 8000 hrs = 28 / 1000 x 8000 x 7/100 = $15.68 Total cost for CFL = 5.71 + 15.68 = $21.39 Incandescent light energy cost for 8000 hrs = 120/ 1000 x 8000 x 7/100 = $67.2 # of Incandescent bulbs required = 8000/800 = 10 bulbs Total cost for Incandescent light = (0.67 x 10) + 67.2 = $73.9 Total Savings = 73.9 21.39 = $52.51 A 100 watt incandescent light bulb is operated for 7 hours, and a 32 watt fluorescent light bulb is operated for the same period of time. At 8 cents per kWh, what is the cost savings in using the fluorescent bulb? Correct D ) 0.04 Incandescent light bulb Energy consumed = 100/1000 x 7 = 0.7 kWh Energy Cost = 0.7 x 8/100 = $0.056 Fluorescent light bulb Energy consumed = 32/1000 x 7 = 0.224 kWh Energy Cost = 0.224 x 8/100 = $0.01792 Savings in Energy Cost = 0.056 0.01792 = $0.03808 Which of the following lighting methods is the most energy efficient? Correct C ) high intensity discharge HID lamps are the most energy efficienct Which one of the following methods of lighting is least efficient? Correct A ) incandescent Incandescent light bulbs are the least efficient Heather is a smart person who wants to save energy and money. So, she has replaced the 75 Watt incandescent light bulb in her house with a 13 Watt CFL bulb. The expected life of incandescent and CFL bulbs is 800 h and 8000 hours respectively. The purchase price of an incandescent bulb is $0.59 and for the CFL it is $5.3...
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This note was uploaded on 09/24/2013 for the course EGEE 102 taught by Professor Pisupati,sarmave during the Spring '07 term at Penn State.
 Spring '07
 PISUPATI,SARMAVE

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