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Topic Ultraviolet radiation
Asked 4 times across 3 UPSC exams over 44 years (1982–2026), peaking in 1982.
Key insights
- Most tested in CSE — 2 of 4 PYQs
- Most asked in 1982
- Recurs across 4 years (1982–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1982 → CDS 2015 → GEO 2026
How the concept evolved
Long-running — most appearances (3 of 4) predate 2016, and it still returns.
Related concepts
Ideas UPSC tests alongside this one — keep exploring.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
GEO2026
Why is sunscreen lotion used while moving out during daytime in summer?
- A To reduce the exposure to all harmful radiations present in sunlight
- B To reduce the exposure to harmful infrared radiations present in sunlight
- C To reduce the exposure to harmful ultraviolet radiations present in sunlight
- D To reflect the visible radiations by the body surface to glow
Answer key not yet available (pending official release)
Science & Technology › Physics & Chemistry
CDS2015
Ozone layer of the Earth's atmosphere is important for living organisms because it
- A prevents entry of ultra-violet rays ✓
- B prevents entry of X-rays
- C maintains level of oxygen on Earth
- D prevents acid rain on Earth
✓ Correct answer: (A)
Environment & Ecology › Pollution & Waste
CSE1993
When there is depletion of ozone in the stratosphere, the wavelength of radiation striking the earth's surface will be
- A 107m
- B 1010m ✓
- C 102m
- D 100 m
✓ Correct answer: (B)
Science & Technology › Physics & Chemistry
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