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Human Eye and Colourful World — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceHuman Eye and Colourful World3 Marks
Question
Why do stars twinkle on a clear night?
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Answer

The light coming from a star undergoes atmospheric refraction due to varying optical densities of air at various altitudes. The continuously changing atmosphere refracts the light from the star by different amounts from one moment to the next. Thus, the star-light reaching our eyes increases and decreases continuously and the star appears to twinkle.

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