13 Jun 2026

Atomic Physics Standard Problems

Standard competitive exam problems in atomic physics with answer key.

atomic-physics gate-2024 csir-net-2023 jest-2022

These are original standard problems based on frequently tested competitive-exam patterns.

Q: The ground state energy of hydrogen is approximately
A: $-13.6\,\mathrm{eV}$
B: $+13.6\,\mathrm{eV}$
C: $-1.6\,\mathrm{eV}$
D: $0\,\mathrm{eV}$
ANSWER: A
NOTE: GATE 2024 style
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Q: Electric dipole transitions require
A: $\Delta l=0$
B: $\Delta l=\pm1$
C: $\Delta m=\pm2$ only
D: $\Delta n=0$ only
ANSWER: B
NOTE: CSIR-NET 2023 style
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Q: The total number of states in a shell with principal quantum number $n$, including spin, is
A: $n$
B: $n^2$
C: $2n^2$
D: $4n^2$
ANSWER: C
NOTE: JEST 2022 style
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Q: The Zeeman effect is splitting of spectral lines in
A: electric field
B: magnetic field
C: gravitational field
D: thermal field
ANSWER: B
NOTE: GATE 2021 style
---
Q: The spin quantum number of an electron is
A: $0$
B: $1/2$
C: $1$
D: $3/2$
ANSWER: B
NOTE: CSIR-NET 2020 style
---
Q: For hydrogen, the wavelength of a Balmer line corresponds to transitions ending at
A: $n=1$
B: $n=2$
C: $n=3$
D: $n=\infty$
ANSWER: B
NOTE: GATE style
---
Q: The fine structure of hydrogen mainly arises from relativistic correction, spin-orbit coupling and
A: Lamb shift only
B: Darwin term
C: blackbody radiation
D: nuclear fission
ANSWER: B
NOTE: CSIR-NET style
---
Q: The Bohr radius is proportional to
A: $\hbar^2$
B: $\hbar^{-2}$
C: $e^2$
D: $m_e$
ANSWER: A
NOTE: JEST style

Problem Sheet Standard MCQs

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