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Topic Electromagnetic radiation
Asked 3 times in CDS over 6 years (2020–2026), peaking in 2025.
Key insights
- Most tested in CDS — 3 of 3 PYQs
- Most asked in 2025
- Recurs across 3 years (2020–2026)
Across exams
CDS · 3How 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.
CDS2026
An X-ray beam can be deflected by :
- A An electric field
- B A magnetic field
- C An electric as well as a magnetic field
- D Neither an electric field nor a magnetic field ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
CDS2025
An X-ray can be deflected :
- A by a magnetic field.
- B by an electric field.
- C by both electric and magnetic field.
- D neither by electric field nor by magnetic field.
Answer key not yet available (pending official release)
Science & Technology › Physics & Chemistry
CDS2020
Which one of the following is not a property of the X-rays?
- A They are deflected by electric fields. ✓
- B They are not deflected by magnetic fields.
- C They have high penetration length in matter.
- D Their wavelength is much smaller than that of visible light.
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
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