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NDA2021General AbilityGeneral ScienceActual

Twinkling of stars is primarily due to the atmospheric

Options

  1. Arefraction
  2. Breflection
  3. Cpolarization
  4. Ddispersion

Correct answer

A. refraction

Step-by-step solution

The twinkling of a star is due to the atmospheric refraction of starlight. The starlight, on entering the earth's atmosphere, undergoes refraction continuously before it reaches the earth. Since the stars are very distant, they approximate point-sized sources of light. As the path of rays of light coming from the star goes on varying slightly, the apparent position of the star fluctuates and the amount of starlight entering eye flickers - the star sometimes appears brighter and sometimes fainter, which is the twink

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