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1 question · 2021 · answers as per the UPSC key
UPSC 2021 · Q72 · Science & Technology › Energy & Environment · Save
With reference to street-lighting, how do sodium lamps differ from LED lamps?
- Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.
- As street-lights, sodium lamps have longer life span than LED lamps.
- The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street-lighting.
Select the correct answer using the code given below.
(a) 3 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Show answer
Answer: (c) 1 and 3 only