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Chapter 28: Q. 39 (page 792)

It seems hard to justify spending \(4.00for a compact fluorescent lightbulb when an ordinary incandescent bulb costs 50垄. To see if this makes sense, compare a 60Wincandescent bulb lasting 1000hours to a 15Wcompact fluorescent bulb having a lifetime of 10,000hours. Both bulbs produce the same amount of visible light and are interchangeable. If electricity costs \)0.10/kWh, what is the total cost鈥攑urchase plus energy鈥� to obtain10,000 hours of light from each type of bulb? This is called the life-cycle cost.

Short Answer

Expert verified

For compact fluorescent lightbulb it will takes $4cost.

But for ordinary bulb it will take$15.

Step by step solution

01

Given information 

We have given,

compact fluorescent lightbulb power and hours = (15W,10,000)

ordinary incandescent bulb power and hours = (60W,1000)

Total electric cost =$0.10/kWh

We have to find the total energy and cost for to obtain 10,000hours of light.

02

Simplify

For a ordinary bulb the total cost will be for10,000hours used,

15W脳10,000hours脳$0.1=0.015KW脳10,000脳$0.1=$15

We can see for the same hours the ordinary bulb using the$15instead of the$4.

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