Learn

Sunday, 25 October

JEE Main · Physics · Class 12

Atoms: JEE Main previous year questions

86 questions in 69 of the 108 JEE Main shifts Lumi analysed, asked in 8 of 8 years. Here is what this chapter tests and how.

Study this chapter
Questions
86
in 69 of 108 shifts · 8 of 8 years
Average a shift
0.8
of 25 Physics · 0.8 since 2024 -0.1
Typical range
0.6–0.9
questions a shift; fewest 0.5, most 1.7
Weighted estimate
0.8
model, recent years count more · about 3 marks
  • Typical range (fact)
  • Average a shift (fact)
  • Weighted estimate (model)

Questions are counted per shift, out of the 25 each subject has, in the shifts Lumi analysed; papers that offered 30 a subject (2017, 2021–2024) are scaled to 25. Typical range: the middle six of the eight years (2017, 2020–2026), leaving out the single highest and lowest year. The average and the range are historical fact. The weighted estimate is a model: each year's share, with recent years counting more (half-life three years), and chapters NTA dropped from the syllabus set near zero. It is a guide to effort, not a forecast of the paper.

What to do

How to spend time on Atoms

Priority

Should do

One of the 10 Physics chapters that took Physics from half to 80% of its questions in the 108 shifts analysed. How bands are set

Past questions
86in 69 of 108 shifts
Study plan gives it
13 hover 12 months; 10 h over 6
Study this chapter →

Ideas asked most often

  1. Energy Level Calculations12×
  2. Rydberg Formula and Spectra10×
  3. Angular Momentum Quantization9×
  4. Shortest and Longest Wavelengths8×
  5. Bohr Orbit Radius6×

26 of the 58 ideas in Lumi’s map of this chapter have not been asked or touched in the shifts analysed. Of its idea-tagged questions from 2024 on, 23% tested an idea not asked in an earlier year, so learn the whole chapter, not just the list above.

Within each subject, chapters in NTA's 2026 syllabus are ranked by their average questions a shift over all 8 years analysed (history, not the model). Going down that list, the chapters that together held the first half of the subject's questions are Must do; the next ones, up to 80%, are Should do; the rest are Lower priority.

Key findings

Atoms at a glance

  1. 01

    77%

    of its 31 questions from 2024 on that Lumi matched to an idea tested one JEE Main had asked in an earlier year; 100% came from a topic asked in an earlier year.

  2. 02

    45%

    of the 58 ideas in Lumi's map of the chapter have not been asked or touched on in the shifts analysed.

  3. 03

    36%

    of its questions asked for a numerical answer, 1.2 times the Physics average.

  4. 04

    3%

    of its questions were rated hard, against 5% across all Physics questions in the same shifts.

Questions a shift, year by year

Out of the 25 Physics questions in a shift. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift.

0241.7’170.5’200.6’210.6’220.9’230.9’240.9’250.6’26

Raw count: 2017: 2 in 1 shift · 2020: 6 in 12 shifts · 2021: 18 in 24 shifts · 2022: 16 in 24 shifts · 2023: 13 in 12 shifts · 2024: 19 in 18 shifts · 2025: 7 in 8 shifts · 2026: 5 in 9 shifts.

Kind of question

SHARE OF QUESTIONS
  • Numerical answer36%
  • Calculation24%
  • Conceptual12%
  • Multi-step8%
  • Application8%
  • Recall, single correct4%
  • Diagram based4%
  • Two statements2%
  • Assertion–reason1%
  • Data or graph1%

Most common asks: ratio of quantity in two orbits (4); trend of energies on transition to higher level (1); wavelength to excite hydrogen-like ion between orbits (1).

Profile

This chapter in numbers

Where it ranks, how steady it is, and what it costs to study.

Rank, all JEE chapters
#54
of 70 by weighted estimate
Rank in Physics
#18
of 28 chapters
Share of Physics
3.3%
of its questions, all shifts analysed
Busiest year
2017
1.7 questions a shift
Year to year
Some swing
varies by about 0.3 questions a shift
Long-run direction
-0.07
questions a shift, per year
Easy questions
55%
3% rated hard
Numerical answer
36%
1.2× the Physics rate
With a figure
7%
graph, diagram or structure
Study time
13 h
10 h on a 6-month plan
Marks per study hour
0.22
#51 of 70 chapters
Foundation for others
97%
of its ideas are used in other chapters

Difficulty, year by year

Each question rated easy, medium or hard. Each bar is that year’s split, so years compare directly; the number is the questions in that year’s analysed shifts (1 to 24 shifts a year).

  • 20172
  • 20206
  • 202118
  • 202216
  • 202313
  • 202419
  • 20257
  • 20265
  • Easy
  • Medium
  • Hard

What it asks you to do

SHARE OF QUESTIONS
  • Calculation52%
  • Multi-step16%
  • Conceptual15%
  • Application8%
  • Recall3%
  • Diagram reading2%
  • Data or graph2%

Coverage

How much of the chapter JEE Main has used

We split the chapter into 58 ideas. In the 108 shifts analysed, JEE Main built a question around 22 of them. Most of the chapter has never been the main idea of a question, so past questions alone leave most of it out.

Asked as the main idea
22
Touched on in a question
10
Never asked
26

Topics

What repeats, topic by topic

This chapter's questions per topic in each year's analysed shifts. The number is the count; the shade is scaled to one shift, so a year with more analysed shifts (1 to 24 a year) does not look darker. 2 questions had no close topic in Lumi's map and count for the chapter only.

’17’20’21’22’23’24’25’26
018+questions in that year’s analysed shifts, shaded per shift
  • Bohr's Atomic Model

    As a topic: 77 questions in 8 of 8 years, most often single correct, 35% numerical answer. Recent asks: numerical: ratio of photon momenta in Balmer lines; numerical: wavelength of hydrogen transition; numerical: ratio of quantity in two orbits.

  • Coulomb's Law

    As a topic: 30 questions in 6 of 8 years, most often single correct, 40% numerical answer.

  • Electric Potential

    As a topic: 29 questions in 7 of 8 years, most often single correct, 38% numerical answer.

  • Magnetic Dipole Moment

    As a topic: 34 questions in 7 of 8 years, most often single correct, 41% numerical answer.

Drill down

Topic, idea, question

Open a topic to see every idea JEE Main tested inside it, then open an idea to read the questions. Each row shows its 8 years.

  • Open77 · 90%51813121774

    22 ideas inside

    • OpenRepeated12 · 16%342
    • OpenRepeated10 · 13%33
    • OpenRepeated9 · 12%322
    • OpenRepeated8 · 10%23
    • OpenRepeated6 · 8%3
    • OpenRepeated5 · 6%22
    • OpenRepeated5 · 6%22
    • OpenRepeated3 · 4%2
    • OpenRepeated2 · 3%
    • Open2 · 3%2
    • OpenRepeated2 · 3%
    • OpenRepeated2 · 3%
    • OpenRepeated2 · 3%
    • Open1 · 1%
    • Open1 · 1%
    • Open1 · 1%
    • Open1 · 1%
    • Open1 · 1%
    • Open1 · 1%
    • Open1 · 1%
    • Open1 · 1%
    • Open1 · 1%
  • Open3 · 3%
  • Open1 · 1%
  • Open1 · 1%
  • Open1 · 1%
  • Open1 · 1%

Squares are the 8 years with analysed shifts, 2017 to 2026. A number is the questions that year when there is more than one; the shade is scaled to one shift, so a year with more analysed shifts (1 to 24 a year) does not look darker. Share is of the level above.

Ideas

The exact ideas JEE Main has asked

Inside the topics, 27 different ideas were tested; 14 came more than once. These are the repeats, then the ideas new since 2024.

Dots are the 8 years with analysed shifts, 2017 to 2026.

Every question

All 86 Atoms questions

Newest first, shift by shift. The newest 40 show their opening words; older ones name the idea they tested. Each opens with its options and the official answer.

JEE Main 20265 questions

  1. 2 Apr 2026, Shift 1 · Q44Angular momentum of an electron in a hydrogen atom is 3hπ\frac{3h}{\pi}, then the energy of the electron is ______ eV.EasySingle correct
  2. 2 Apr 2026, Shift 2 · Q47Using Bohr's model, calculate the ratio of the magnetic fields generated due to the motion of the electrons in the 2nd and 4th orbits of…MediumNumerical value
  3. 4 Apr 2026, Shift 2 · Q43In Rutherford's alpha-particle scattering experiment, only a few alpha particles rebound back because A. The size of gold nucleus is very…MediumOther
  4. 5 Apr 2026, Shift 1 · Q36In the hydrogen atom, the electron makes a transition from the higher orbit (ii) to a lower orbit (ff). The ratio of the radius of the…EasySingle correct
  5. 6 Apr 2026, Shift 1 · Q44The ratio of momentum of the photons of the 1st1^{\mathrm{st}} and 2nd2^{\mathrm{nd}} line of Balmer series of Hydrogen atoms is…MediumSingle correct

JEE Main 20257 questions

  1. 2 Apr 2025, Shift 1 · Q43Considering Bohr's atomic model for hydrogen atom : (A) the energy of H atom in ground state is same as energy of He+\mathrm{He^+} ion in…EasyOther
  2. 2 Apr 2025, Shift 2 · Q40Assuming the validity of Bohr's atomic model for hydrogen like ions the radius of Li++\mathrm{Li^{++}} ion in its ground state is given by…EasySingle correct
  3. 3 Apr 2025, Shift 2 · Q44Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A : The Bohr model is…EasyAssertion–reason
  4. 3 Apr 2025, Shift 2 · Q50An electron in the hydrogen atom initially in the fourth excited state makes a transition to nth\mathrm{n^{th}} energy state by emitting a…EasyNumerical value
  5. 4 Apr 2025, Shift 2 · Q41Given below are two statements : Statement (I) : The dimensions of Planck's constant and angular momentum are same. Statement (II) : In…EasyTwo statements
  6. 7 Apr 2025, Shift 1 · Q43For a hydrogen atom, the ratio of the largest wavelength of Lyman series to that of the Balmer series isEasySingle correct
  7. 7 Apr 2025, Shift 1 · Q44In a hydrogen like ion, the energy difference between the 2nd2^{\mathrm{nd}} excitation energy state and ground is 108.8 eV. The atomic…EasySingle correct

JEE Main 202419 questions

  1. 4 Apr 2024, Shift 1 · Q60A hydrogen atom changes its state from n = 3 to n = 2. Due to recoil, the percentage change in the wave length of emitted light is…HardNumerical value
  2. 4 Apr 2024, Shift 2 · Q48According to Bohr's theory, the moment of momentum of an electron revolving in 4th^{th} orbit of hydrogen atom is:EasySingle correct
  3. 5 Apr 2024, Shift 1 · Q48An electron rotates in a circle around a nucleus having positive charge Ze. Correct relation between total energy (E) of electron to its…EasySingle correct
  4. 5 Apr 2024, Shift 2 · Q48The angular momentum of an electron in a hydrogen atom is proportional to : (Where r is the radius of orbit of electron)EasySingle correct
  5. 5 Apr 2024, Shift 2 · Q60The shortest wavelength of the spectral lines in the Lyman series of hydrogen spectrum is 915 A˚\mathrm{\AA}. The longest wavelength of…MediumNumerical value
  6. 6 Apr 2024, Shift 1 · Q48The ratio of the shortest wavelength of Balmer series to the shortest wavelength of Lyman series for hydrogen atom is :EasySingle correct
  7. 6 Apr 2024, Shift 1 · Q60Radius of a certain orbit of hydrogen atom is 8.48 Å. If energy of electron in this orbit is E/xE/x, then xx = __________. (Given aoa_o =…EasyNumerical value
  8. 6 Apr 2024, Shift 2 · Q48The longest wavelength associated with Paschen series is : (Given RH=1.097×107R_H=1.097\times10^7 SI unit)EasySingle correct
  9. 6 Apr 2024, Shift 2 · Q55In Franck-Hertz experiment, the first dip in the current-voltage graph for hydrogen is observed at 10.2 V. The wavelength of light emitted…EasyNumerical value
  10. 8 Apr 2024, Shift 1 · Q58In an alpha particle scattering experiment distance of closest approach for the α\alpha particle is 4.5×10−144.5\times10^{-14} m. If target…MediumNumerical value
  11. 9 Apr 2024, Shift 2 · Q35A hydrogen atom in ground state is given an energy of 10.210.2 eV. How many spectral lines will be emitted due to transition of electrons ?EasySingle correct
  12. 1 Feb 2024, Shift 1 · Q47The minimum energy required by a hydrogen atom in ground state to emit radiation in Balmer series is nearly :MediumSingle correct
  13. 1 Feb 2024, Shift 2 · Q60A particular hydrogen - like ion emits the radiation of frequency 3×10153\times10^{15} Hz when it makes transition from n = 2 to n = 1. The…MediumNumerical value
  14. 27 Jan 2024, Shift 1 · Q47The radius of third stationary orbit of electron for Bohr's atom is R. The radius of fourth stationary orbit will be :EasySingle correct
  15. 29 Jan 2024, Shift 1 · Q60When a hydrogen atom going from nn=2 to nn=1 emits a photon, its recoil speed is x5 m/s\frac{x}{5}\ m/s. Where xx = ______. (Use, mass of…MediumNumerical value
  16. 30 Jan 2024, Shift 1 · Q47The ratio of the magnitude of the kinetic energy to the potential energy of an electron in the 5th5^{\mathrm{th}} excited state of a…EasySingle correct
  17. 30 Jan 2024, Shift 1 · Q60A electron of hydrogen atom on an excited state is having energy En=−0.85E_n = -0.85 eV. The maximum number of allowed transitions to lower…EasyNumerical value
  18. 30 Jan 2024, Shift 2 · Q48An electron revolving in nthn^{\mathrm{th}} Bohr orbit has magnetic moment μn\mu_n. If μn∝nx\mu_n \propto n^x, the value of xx isEasySingle correct
  19. 31 Jan 2024, Shift 1 · Q47If the wavelength of the first member of Lyman series of hydrogen is λ\lambda. The wavelength of the second member will beEasySingle correct

JEE Main 202313 questions

  1. 6 Apr 2023, Shift 1 · Q34The energy levels of an hydrogen atom are shown below. The transition corresponding to emission of shortest wavelength isEasyDiagram basedHas a figure
  2. 6 Apr 2023, Shift 1 · Q53The radius of fifth orbit of the Li++\mathrm{Li^{++}} is ____________ ×10−12\times10^{-12} m. Take: radius of hydrogen atom = 0.51 ÅEasyNumerical value
  3. 6 Apr 2023, Shift 2 · Q43A small particle of mass mm moves in such a way that its potential energy U=12mω2r2U=\frac{1}{2}m\omega^2 r^2 where ω\omega is constant and rr…MediumSingle correct
  4. 6 Apr 2023, Shift 2 · Q56Experimentally it is found that 12.8 eV energy is required to separate a hydrogen atom into a proton and an electron. So the orbital…MediumNumerical value
  5. 8 Apr 2023, Shift 2 · Q56The ratio of wavelength of spectral lines Hα\mathrm{H}_\alpha and Hβ\mathrm{H}_\beta in the Balmer series is x20\frac{x}{20}. The value of…EasyNumerical value
  6. 10 Apr 2023, Shift 1 · Q44The angular momentum for the electron in Bohr's orbit is LL. If the electron is assumed to revolve in second orbit of hydrogen atom, then…EasySingle correct
  7. 10 Apr 2023, Shift 2 · Q56If 917 A˚\mathrm{\AA} be the lowest wavelength of Lyman series then the lowest wavelength of Balmer series will be ____________…EasyNumerical value
  8. 11 Apr 2023, Shift 1 · Q51A monochromatic light is incident on a hydrogen sample in ground state. Hydrogen atoms absorb a fraction of light and subsequently emit…MediumNumerical value
  9. 11 Apr 2023, Shift 2 · Q44The energy of He+\mathrm{He^+} ion in its first excited state is, (The ground state energy for the Hydrogen atom is −13.6 eV-13.6\ \mathrm{eV}):EasySingle correct
  10. 12 Apr 2023, Shift 1 · Q48Number of Spectral Lines · Medium · Single correct
  11. 13 Apr 2023, Shift 1 · Q51Bohr Orbit Radius · Easy · Numerical value
  12. 13 Apr 2023, Shift 2 · Q60Photon Energy and Momentum · Medium · Numerical value
  13. 15 Apr 2023, Shift 1 · Q56Rydberg Formula and Spectra · Medium · Numerical value · has a figure

JEE Main 202216 questions

  1. 25 Jul 2022, Shift 1 · Q48Angular Momentum Quantization · Easy · Single correct
  2. 25 Jul 2022, Shift 2 · Q50Rydberg Formula and Spectra · Medium · Single correct
  3. 25 Jul 2022, Shift 2 · Q54Rydberg Formula and Spectra · Easy · Numerical value
  4. 26 Jul 2022, Shift 1 · Q59Rydberg Formula and Spectra · Medium · Numerical value
  5. 29 Jul 2022, Shift 1 · Q47Energy Level Calculations · Easy · Single correct
  6. 30 Jul 2022, Shift 2 · Q17Bohr Orbit Radius · Easy · Single correct
  7. 30 Jul 2022, Shift 2 · Q21Distance of Closest Approach · Medium · Numerical value
  8. 24 Jun 2022, Shift 1 · Q44Open the question · Easy · Single correct
  9. 24 Jun 2022, Shift 2 · Q50Energy Ratios in Bohr Orbits · Easy · Single correct
  10. 25 Jun 2022, Shift 1 · Q46Electron Velocity in Orbit · Easy · Single correct
  11. 27 Jun 2022, Shift 1 · Q48Angular Momentum Quantization · Easy · Single correct
  12. 27 Jun 2022, Shift 1 · Q54Energy Level Calculations · Medium · Numerical value
  13. 27 Jun 2022, Shift 2 · Q48Energy Level Calculations · Easy · Two statements
  14. 29 Jun 2022, Shift 1 · Q57Coulomb Force in Rutherford Scattering · Medium · Numerical value
  15. 30 Jun 2022, Shift 1 · Q50Angular Momentum Quantization · Medium · Single correct
  16. 30 Jun 2022, Shift 1 · Q59Energy Level Calculations · Medium · Numerical value

JEE Main 202118 questions

  1. 3 Aug 2021, Shift 2 · Q23Shortest and Longest Wavelengths · Medium · Numerical value
  2. 4 Aug 2021, Shift 1 · Q3Energy Level Calculations · Medium · Single correct
  3. 4 Aug 2021, Shift 1 · Q5Magnetic Field and Dipole Moment · Hard · Single correct
  4. 4 Aug 2021, Shift 2 · Q2Energy Ratios in Bohr Orbits · Medium · Other
  5. 4 Aug 2021, Shift 2 · Q30Energy Ratios in Bohr Orbits · Medium · Numerical value
  6. 26 Aug 2021, Shift 1 · Q5Rydberg Formula and Spectra · Easy · Single correct
  7. 27 Aug 2021, Shift 2 · Q29Number of Spectral Lines · Easy · Numerical value
  8. 31 Aug 2021, Shift 2 · Q2Energy Level Calculations · Medium · Single correct
  9. 24 Feb 2021, Shift 1 · Q17Shortest and Longest Wavelengths · Medium · Diagram based · has a figure
  10. 24 Feb 2021, Shift 2 · Q17Energy Level Calculations · Easy · Single correct
  11. 25 Feb 2021, Shift 2 · Q16Rydberg Formula and Spectra · Easy · Single correct
  12. 26 Feb 2021, Shift 1 · Q19Rydberg Formula and Spectra · Medium · Single correct
  13. 26 Feb 2021, Shift 2 · Q14Atom Recoil During Emission · Medium · Single correct
  14. 17 Mar 2021, Shift 1 · Q14Scaling for Hydrogenic Ions · Easy · Single correct
  15. 17 Mar 2021, Shift 1 · Q20Electron Velocity in Orbit · Easy · Single correct
  16. 17 Mar 2021, Shift 2 · Q13Spectral Series EM Regions · Easy · Single correct
  17. 17 Mar 2021, Shift 2 · Q29Angular Momentum Quantization · Medium · Numerical value
  18. 18 Mar 2021, Shift 1 · Q10Reduced Mass Effect · Medium · Single correct

JEE Main 20206 questions

  1. 8 Jan 2020, Shift 1 · Q18Open the question · Medium · Diagram based · has a figure
  2. 8 Jan 2020, Shift 2 · Q25Rydberg Formula and Spectra · Easy · Numerical value
  3. 9 Jan 2020, Shift 2 · Q19Identifying Atomic Number from Spectra · Medium · Single correct
  4. 2 Sep 2020, Shift 2 · Q18Bohr's Correspondence Principle · Medium · Single correct
  5. 4 Sep 2020, Shift 1 · Q25Shortest and Longest Wavelengths · Medium · Numerical value
  6. 5 Sep 2020, Shift 1 · Q21Collisional Excitation · Hard · Numerical value

JEE Main 20172 questions

  1. 2 Apr 2017 (offline) · Q21Cutoff Wavelength Shortcut Formula · Medium · Single correct · has a figure
  2. 2 Apr 2017 (offline) · Q25Wavelengths in Cascade Transitions · Easy · Single correct · has a figure

Questions from the official JEE Main papers published by NTA. Chapter, topic and idea tags, counts and notes are Lumi’s. Pattern: Asked most years.

More Physics, Class 12

All JEE Main chaptersJEE Main Physics analysisStudy plan