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  9. Q9

RRB NTPC 2021 · Question 9 of 131

The blue colour of the sky is due to the:

  1. Adispersion of light
  2. Bscattering of lightCorrect
  3. Crefraction of light
  4. Ddiffraction of light

Answer: B. scattering of light

Explanation

Blue colour of the sky is due to scattering of light. The two most common types of matter present in the atmosphere are gaseous nitrogen and oxygen. These particles are most effective in scattering the higher frequency and shorter wavelength portions of the visible light spectrum.

Source: RRB NTPC 2021 CBT 1 Previous Year Paper (3 Feb) — ixambee compilation with answer key · reliable-secondary

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