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Topic Image formation
Asked 5 times across 2 UPSC exams over 7 years (2014–2021), peaking in 2020.
Key insights
- Most tested in CDS — 3 of 5 PYQs
- Most asked in 2020
- Recurs across 3 years (2014–2021)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CDS 2014 → NDA 2020
How the concept evolved
Rising — more than half its appearances (4 of 5) are since 2016.
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.
CDS2021
Where should an object be placed in front of a convex lens to get a real and enlarged image of the object?
- A At twice the focal length
- B At infinity
- C Between the principal focus and twice the focal length ✓
- D Beyond twice the focal length
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
NDA2021
The image we see in plane mirror is
- A real and thus can be photographed.
- B virtual and nearer than the object.
- C virtual and is laterally inverted. ✓
- D real but cannot be photographed.
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
CDS2020
A luminous object is placed at a distance of 40 cm from a converging lens of focal length 25 cm. The image obtained in the screen is
- A erect and magnified
- B erect and smaller
- C inverted and magnified ✓
- D inverted and smaller
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
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