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Topic Ozone layer
Asked 9 times across 3 UPSC exams over 42 years (1982–2024), peaking in 1982.
Key insights
- Most tested in CSE — 4 of 9 PYQs
- Most asked in 1982
- Recurs across 9 years (1982–2024)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1982 → CDS 2015 → GEO 2024
How the concept evolved
182
186
187
193
115
117
120
121
124
Long-running — most appearances (5 of 9) 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.
GEO2024
In which sphere of the atmosphere is harmful ultraviolet (UV) radiation from the Sun absorbed ?
- A Mesosphere
- B Thermosphere
- C Troposphere
- D Stratosphere ✓
✓ Correct answer: (D)
Geography › Climatology
CDS2021
Ozone layer, which absorbs the ultra-violet radiation, is found in which one of the following layers of the atmosphere?
- A Ionosphere
- B Troposphere
- C Mesosphere
- D Stratosphere ✓
✓ Correct answer: (D)
Geography › Climatology
CDS2020
Which one of the following statements with regard to ozone is not correct?
- A Ozone is found mostly in 15-55 km in the atmosphere.
- B Ozone is produced by gaseous chemical reactions.
- C 16th November is celebrated as the International Day for the Preservation of the Ozone Layer. ✓
- D Ozone is a form of oxygen in which three oxygen atoms are bounded together.
✓ Correct answer: (C)
Environment & Ecology › Pollution & Waste
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