Question
Download Solution PDFWhich of the following lamps is well suited for street lightning in terms of high luminous efficiency?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFLuminous Efficiency of lamps:
Lamp |
Lamp efficiency |
Carbon filament lamp |
3-5 lumen/watt |
Incandescent lamp |
8-40 lumen/watt |
Neon lamp |
15-40 lumen/watt |
Fluorescent lamp |
40-60 lumen/watt |
Vacuum lamp |
30-40 lumen/watt |
Gas-filled lamp |
12 lumen/watt |
Arc lamp |
9-12 lumen/watt |
Sodium vapor lamp |
100-175 lumen/watt |
- Sodium vapor light lamps are most suitable for street lighting because they emit yellow light which is the easiest color to recognize in the night or darkness.
- It can last up to 24,000 hours, which is about four times as long as mercury vapor lamps and 24 times as long as incandescent lamps.
- It does not require frequent replacement or cleaning, which reduces labor and disposal costs.
- It can produce up to 150 lumens per watt, which is about twice as much as mercury vapor lamps and five times as much as incandescent lamps.
Additional Information
Application of different lamps:
Types of Lamp |
Application |
Neon lamps |
visual indicators in electronic equipment and appliances |
Fluorescent lamps |
commercial lighting, industrial lighting, classroom lighting, |
Sodium vapor lamp |
roadways, parking lots, security areas, airports, goods yards |
Carbon arc lamp |
cinema projector, searchlight, flash camera |
Last updated on May 29, 2025
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