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Topic Wave-particle duality
Asked 2 times across 2 UPSC exams over 4 years (2020–2024), peaking in 2020.
Key insights
- Most tested in CAPF — 1 of 2 PYQs
- Most asked in 2020
- Recurs across 2 years (2020–2024)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CAPF 2020 → GEO 2024
How the concept evolved
Rising — more than half its appearances (2 of 2) are since 2016.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
GEO2024
Which one of the following experiments explains the wave nature of electromagnetic radiation ?
- A Black-body radiation
- B Photoelectric effect
- C Rutherford's scattering experiment
- D Diffraction of light ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
CAPF2020
An electron and a photon have same de Broglie wavelength. It implies that they have the same
- A linear momentum ✓
- B energy
- C speed
- D angular momentum
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
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