Topic Light
Asked 3 times across 2 UPSC exams over 2 years (2021–2023), peaking in 2021.
Key insights
- Most tested in NDA — 2 of 3 PYQs
- Most asked in 2021
- Recurs across 2 years (2021–2023)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
NDA 2021 → CDS 2023
How the concept evolved
Rising — more than half its appearances (3 of 3) 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.
CDS2023
Which one of the following statements is correct regarding the travel of a light beam from a rare to a dense medium ?
- A A light beam travelling from a rare medium to a dense medium slows down and bends towards the normal. ✓
- B A light beam travelling from a rare medium to a dense medium speeds up and bends towards the normal.
- C A light beam travelling from a rare medium to a dense medium slows down and bends away from the normal.
- D A light beam travelling from a rare medium to a dense medium speeds up and bends away from the normal.
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
NDA2021
Which one of the following colours may be obtained by combining green and red colours ?
- A Blue
- B Magenta
- C Pink
- D Yellow ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
NDA2021
Which of the following are the primary colours of light ?
- A Yellow, Red and Green
- B Blue, Red and Green ✓
- C Violet, Red and Yellow
- D Indigo, Violet and Green
✓ Correct answer: (B)
Science & Technology › Physics & Chemistry
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