Engineering Fundamentals: An Introduction to Engineering
6th Edition
ISBN: 9780357112311
Author: Saeed Moaveni
Publisher: Cengage Learning US
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Chapter 12, Problem 31P
To determine
Which light is efficient one for running at 4 hours per day for 300 days.
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Determine the luminous efficacy of the following lamps having comparable illumination outputs:a. A 300 W incandescent lamp that emits 5820 lmb. Two 32 W linear fluorescent lamps that emit 2950 lm per lamp in a luminaire that consumes 70 W including the ballastsc. A 70 W metal halide lamp that consumes 88 W, including the ballast and emits 5500 lm
The PureNSafe Company is designing a solar-driven, portable water disinfection system to be used by the military. The system is simply an inlet tube, a pump, a well-mixed chamber, and an outlet tube. Water is pumped continuously into the chamber where it is irradiated with UV light before exiting through the outlet tube into a collection vessel. The disinfection rate constant for UV light is 7.50 s-1, and the number of bacteria in the water must be reduced by 3.5 logs. Because the military needs the unit to fit into a backpack, they require that the unit’s chamber be no larger than 2.00 L.
a) How much water will the system be able to produce during 10 hours of sunlight?
b) If instead of a well-mixed chamber, the backpack unit is designed using coiled tubing (2.00 L total volume), how much water will the system be able to produce during 10 hours of sunlight?
2. A parallel-plate capacitor initially has a capacitance of 100 F. What will be the
capacitance if the distance between the plates is doubled?
Chapter 12 Solutions
Engineering Fundamentals: An Introduction to Engineering
Ch. 12.1 - In what unit is electric current measured?Ch. 12.1 - Prob. 2BYGCh. 12.1 - Prob. 3BYGCh. 12.1 - Prob. 4BYGCh. 12.1 - Prob. 5BYGCh. 12.1 - Prob. BYGVCh. 12.2 - Prob. 1BYGCh. 12.2 - Prob. 2BYGCh. 12.2 - Prob. 3BYGCh. 12.2 - Prob. 4BYG
Ch. 12.2 - Prob. 5BYGCh. 12.2 - Prob. 6BYGCh. 12.2 - Prob. BYGVCh. 12.5 - Prob. 1BYGCh. 12.5 - Prob. 2BYGCh. 12.5 - Prob. 3BYGCh. 12.5 - Prob. 4BYGCh. 12.5 - Prob. 5BYGCh. 12.5 - Prob. 6BYGCh. 12.5 - Prob. BYGVCh. 12 - Prob. 1PCh. 12 - Prob. 2PCh. 12 - Prob. 3PCh. 12 - Prob. 6PCh. 12 - Prob. 7PCh. 12 - Prob. 8PCh. 12 - Prob. 9PCh. 12 - Prob. 10PCh. 12 - Prob. 13PCh. 12 - Prob. 16PCh. 12 - Prob. 18PCh. 12 - Prob. 19PCh. 12 - Prob. 20PCh. 12 - Prob. 21PCh. 12 - Prob. 23PCh. 12 - Prob. 24PCh. 12 - As you know, a fuse is a safety device that is...Ch. 12 - Prob. 27PCh. 12 - Prob. 28PCh. 12 - Prob. 29PCh. 12 - Prob. 30PCh. 12 - Prob. 31PCh. 12 - Prob. 33PCh. 12 - Prob. 34PCh. 12 - Prob. 35PCh. 12 - Prob. 36PCh. 12 - Prob. 37P
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