Home / Person / James Chadwick
Person James Chadwick
Asked 4 times across 2 UPSC exams over 37 years (1988–2025), peaking in 1988.
Key insights
- Most tested in NDA — 3 of 4 PYQs
- Most asked in 1988
- Recurs across 4 years (1988–2025)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1988 → NDA 2020
How the concept evolved
Rising — more than half its appearances (3 of 4) 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.
NDA2025
Which one of the following particles in the nucleus of an atom was discovered by J. Chadwick?
- A Electron
- B Proton
- C Positron
- D Neutron ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
NDA2021
Which of the following pairs of physical phenomenon and the discoverer is/are correctly matched ?
- James Chadwick : Photoelectric effect
- Albert Einstein : Neutron
- Marie Curie : Radium
Select the correct answer using the code given below :
- A 1, 2 and 3
- B 1 and 2 only
- C 2 and 3 only
- D 3 only ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
NDA2020
Neutrons were discovered by
- A James Chadwick
- B Ernest Rutherford
- C J. J. Thomson ✓
- D John Dalton
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
Study how UPSC repeats — not just the papers
₹199 / 1 year · Founding Member
Full access unlocks the three things no PYQ PDF gives you:
① Cross-exam learning — see the same idea recur across CSE, CAPF, CDS and NDA.
② Topic evolution — how each idea is framed, year by year.
③ Question intelligence — every PYQ + answer, linked to related concepts and similar questions.
e.g. Round Table Conference: CDS 2017 → CSE 2017 → … → CAPF 2024
15 days free, no card required — then ₹199 for 1 year.
Start your 15-day free trial →