gs1medium

With reference to street-lighting, how do sodium lamps differ from LED lamps?

  1. 1.Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.
  2. 2.As street-lights, sodium lamps have a longer lifespan than LED lamps.
  3. 3.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.

  1. A.3 only
  2. B.2 only
  3. C.1 and 3 only
  4. D.1, 2 and 3
▶ Answer & Explanation

Correct answer: C. 1 and 3 only

Sodium vapour lamps emit light omnidirectionally, often requiring reflectors to direct light downwards, whereas LED lamps are inherently directional, producing light in a more focused beam. Sodium lamps produce a characteristic yellowish light, which is nearly monochromatic and can distort colour perception. LED lamps offer a broader spectrum of light, enabling better colour rendering and improved visibility, which is crucial for identifying objects and hazards.

Source: UPSC gs1 2021

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