GyanGramQuestion
Consider the following phenomena:
1. Size of the sun at dusk
2. Colour of the sun at dawn
3. Moon being visible at dawn
4. The twinkle of stars in the sky
5. Polestar being visible in the sky
Which of the above are optical illusions?
PRELIMS 2013 · SCIENCE & TECHNOLOGY
Consider the following phenomena: 1. Size of the sun at dusk 2. Colour of the sun at dawn…
Attempt this previous-year question. The correct option stays hidden until you choose.
Pick an option to check yourself.
• Correct Answer: C
• Sun appearing larger at horizon (Moon illusion), red colour at dawn (Rayleigh scattering perception), and star twinkling (atmospheric scintillation) are optical phenomena.
• Moon visible at dawn is real astronomical positioning; Polestar visibility is real due to axial alignment.
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