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Sunday, 25 October

JEE Main · Physics · Class 11

Thermodynamics: JEE Main previous year questions

114 questions in 93 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
114
in 93 of 108 shifts · 8 of 8 years
Average a shift
1.0
of 25 Physics · 1.1 since 2024 0.2
Typical range
0.8–1.1
questions a shift; fewest 0.7, most 1.4
Weighted estimate
1.0
model, recent years count more · about 4.1 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 Thermodynamics

Priority

Must do

One of the 11 Physics chapters that together held the first half of Physics questions in the 108 shifts analysed. How bands are set

Past questions
114in 93 of 108 shifts
Study plan gives it
17 hover 12 months; 13 h over 6
Study this chapter →

Ideas asked most often

  1. Adiabatic Process Analysis16×
  2. Carnot Efficiency Limit15×
  3. Cyclic Process Work7×
  4. Heat in Isochoric and Isobaric Processes5×
  5. Adiabatic T-V and P-T Relations5×

162 of the 223 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, 24% 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

Thermodynamics at a glance

  1. 01

    76%

    of its 38 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

    73%

    of the 223 ideas in Lumi's map of the chapter have not been asked or touched on in the shifts analysed.

  3. 03

    20%

    of its questions asked for a numerical answer, 0.7 times the Physics average.

  4. 04

    7%

    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.

0240.8’171’201’210.8’220.7’230.8’241.4’251.1’26

Raw count: 2017: 1 in 1 shift · 2020: 12 in 12 shifts · 2021: 30 in 24 shifts · 2022: 23 in 24 shifts · 2023: 10 in 12 shifts · 2024: 17 in 18 shifts · 2025: 11 in 8 shifts · 2026: 10 in 9 shifts.

Kind of question

SHARE OF QUESTIONS
  • Calculation31%
  • Numerical answer20%
  • Diagram based12%
  • Multi-step11%
  • Conceptual11%
  • Application6%
  • Match the list4%
  • Two statements4%
  • Recall, single correct1%
  • Data or graph1%

Most common asks: match list on thermodynamic processes (4); work done in adiabatic expansion (2); net work in cyclic process on p-v diagram (2).

Profile

This chapter in numbers

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

Rank, all JEE chapters
#37
of 70 by weighted estimate
Rank in Physics
#8
of 28 chapters
Share of Physics
3.8%
of its questions, all shifts analysed
Busiest year
2025
1.4 questions a shift
Year to year
Steady
varies by about 0.2 questions a shift
Long-run direction
+0.03
questions a shift, per year
Easy questions
46%
7% rated hard
Numerical answer
20%
0.7× the Physics rate
With a figure
18%
graph, diagram or structure
Study time
17 h
13 h on a 6-month plan
Marks per study hour
0.24
#27 of 70 chapters
Foundation for others
57%
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).

  • 20171
  • 202012
  • 202130
  • 202223
  • 202310
  • 202417
  • 202511
  • 202610
  • Easy
  • Medium
  • Hard

What it asks you to do

SHARE OF QUESTIONS
  • Calculation44%
  • Multi-step20%
  • Conceptual17%
  • Data or graph8%
  • Application6%
  • Recall4%
  • Diagram reading1%

Coverage

How much of the chapter JEE Main has used

We split the chapter into 223 ideas. In the 108 shifts analysed, JEE Main built a question around 48 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
48
Touched on in a question
13
Never asked
162

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
011+questions in that year’s analysed shifts, shaded per shift
  • Thermodynamic Processes

    As a topic: 52 questions in 7 of 8 years, most often single correct, 17% numerical answer. Recent asks: numerical: final volume in adiabatic piston compartments; order/ranking of work in isothermal processes; ratio of heat, energy change and work in isobaric process.

  • First Law of Thermodynamics

    As a topic: 40 questions in 8 of 8 years, most often single correct, 35% numerical answer.

  • Heat Engines and Refrigerators

    As a topic: 22 questions in 4 of 8 years, most often single correct, 27% numerical answer.

  • Kinetic Theory of Gases

    As a topic: 84 questions in 8 of 8 years, most often single correct, 13% numerical answer. Recent asks: statement I/II on ideal gas internal energy; assertion-reason on kinetic theory of gases; numerical: ratio of kinetic energies of gases.

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.

  • Open45 · 39%71164872

    13 ideas inside

    • OpenRepeated16 · 36%33233
    • OpenRepeated6 · 13%22
    • OpenRepeated5 · 11%2
    • OpenRepeated5 · 11%32
    • OpenRepeated3 · 7%2
    • OpenRepeated3 · 7%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
  • Open33 · 29%574727
  • Open22 · 19%4882
  • Open5 · 4%2
  • Open4 · 4%22
  • Open2 · 2%
  • 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, 43 different ideas were tested; 18 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 114 Thermodynamics 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 202610 questions

  1. 2 Apr 2026, Shift 1 · Q33Heat is supplied to a diatomic gas at constant pressure. Then the ratio of ΔQ:ΔU:ΔW\Delta Q : \Delta U : \Delta W is ______.EasySingle correct
  2. 2 Apr 2026, Shift 1 · Q47A vessel contains 0.15 m30.15\ \mathrm{m^3} of a gas at pressure 88 bar and temperature 140 ∘140\ ^\circC with cp=3Rc_p=3R and cv=2Rc_v=2R. It is…MediumNumerical value
  3. 2 Apr 2026, Shift 2 · Q485 moles of unknown gas is heated at constant volume from 10°C to 20°C. The molar specific heat of this gas at constant pressure cp=8c_p = 8…MediumNumerical value
  4. 5 Apr 2026, Shift 1 · Q32Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Statement I: Change in internal…MediumTwo statements
  5. 5 Apr 2026, Shift 1 · Q33Consider the following statements: A. Zeroth law of thermodynamics gives concept of temperature B. First law of thermodynamics gives…MediumOther
  6. 6 Apr 2026, Shift 1 · Q50A certain gas is isothermally compressed to (13)rd\left(\frac{1}{3}\right)^{\mathrm{rd}} of its initial volume (V0=3V_0=3 litre) by applying…MediumNumerical value
  7. 6 Apr 2026, Shift 2 · Q30A cylinder with adiabatic walls is closed at both ends and is divided into two compartments by a frictionless adiabatic piston. Ideal gas…HardSingle correct
  8. 6 Apr 2026, Shift 2 · Q35If 2 mole of an ideal monoatomic gas at temperature TT, is mixed with 6 mole of another ideal monoatomic gas at temperature 2T2T then the…EasySingle correct
  9. 8 Apr 2026, Shift 2 · Q35One mole of diatomic gas having rotational modes only is kept in a cylinder with a piston system. The cross-section area of the cylinder…MediumSingle correct
  10. 8 Apr 2026, Shift 2 · Q36Initial pressure and volume of a monoatomic ideal gas are PP and VV. The change in internal energy of this gas in adiabatic expansion to…MediumSingle correct

JEE Main 202511 questions

  1. 2 Apr 2025, Shift 1 · Q31In an adiabatic process, which of the following statements is true ?EasySingle correct
  2. 2 Apr 2025, Shift 2 · Q32Identify the characteristics of an adiabatic process in a monoatomic gas. (A) Internal energy is constant. (B) Work done in the process is…MediumOther
  3. 3 Apr 2025, Shift 1 · Q33During the melting of a slab of ice at 273 K at atmospheric pressure:MediumSingle correct
  4. 3 Apr 2025, Shift 1 · Q34A gas is kept in a container having walls which are thermally non-conducting. Initially the gas has a volume of 800 cm3800\ \mathrm{cm^3} and…EasySingle correct
  5. 3 Apr 2025, Shift 1 · Q35A piston of mass M is hung from a massless spring whose restoring force law goes as F=−kx3F = -kx^3, where k is the spring constant of…HardDiagram basedHas a figure
  6. 3 Apr 2025, Shift 2 · Q33An ideal gas exists in a state with pressure P0\mathrm{P_0}, volume V0\mathrm{V_0}. It is isothermally expanded to 4 times of its initial…MediumSingle correct
  7. 4 Apr 2025, Shift 2 · Q33Match List - I with List - II. List - I List - II (A) Isobaric (I) ΔQ=ΔW\Delta Q=\Delta W (B) Isochoric (II) ΔQ=ΔU\Delta Q=\Delta U (C)…EasyMatch the list
  8. 7 Apr 2025, Shift 1 · Q33Match the LIST-I with LIST-I LIST-I | LIST-II A. Triatomic rigid gas | I. CpCv=53\frac{C_p}{C_v} = \frac{5}{3} B. Diatomic non-rigid gas | II.…MediumMatch the list
  9. 7 Apr 2025, Shift 1 · Q48An ideal gas has undergone through the cyclic process as shown in the figure. Work done by the gas in the entire cycle is _______…MediumNumerical valueHas a figure
  10. 7 Apr 2025, Shift 2 · Q34Match List - I with List - II. List - I | List - II (A) Isothermal | (I) ΔW\Delta W (work done) =0=0 (B) Adiabatic | (II) ΔQ\Delta Q…EasyMatch the list
  11. 8 Apr 2025, Shift 2 · Q33A monoatomic gas having γ=53\gamma = \frac{5}{3} is stored in a thermally insulated container and the gas is suddenly compressed to…EasySingle correct

JEE Main 202417 questions

  1. 4 Apr 2024, Shift 2 · Q39A sample of gas at temperature TT is adiabatically expanded to double its volume. Adiabatic constant for the gas is γ=3/2\gamma = 3/2. The…MediumSingle correct
  2. 5 Apr 2024, Shift 1 · Q38The heat absorbed by a system in going through the given cyclic process is :MediumDiagram basedHas a figure
  3. 5 Apr 2024, Shift 2 · Q49During an adiabatic process, if the pressure of a gas is found to be proportional to the cube of its absolute temperature, then the ratio…MediumSingle correct
  4. 6 Apr 2024, Shift 1 · Q36The specific heat at constant pressure of a real gas obeying PV2=RTPV^2 = RT equation is:HardSingle correct
  5. 6 Apr 2024, Shift 2 · Q39A total of 48 J heat is given to one mole of helium kept in a cylinder. The temperature of helium increases by 2∘C2^\circ\mathrm{C}. The…EasySingle correct
  6. 8 Apr 2024, Shift 1 · Q37Two different adiabatic paths for the same gas intersect two isothermal curves as shown in P-V diagram. The relation between the ratio…MediumSingle correctHas a figure
  7. 8 Apr 2024, Shift 2 · Q38A diatomic gas (γ=1.4\gamma=1.4) does 100 J of work in an isobaric expansion. The heat given to the gas is :EasySingle correct
  8. 9 Apr 2024, Shift 1 · Q38A sample of 11 mole gas at temperature T is adiabatically expanded to double its volume. If adiabatic constant for the gas is…MediumSingle correct
  9. 9 Apr 2024, Shift 1 · Q39The volume of an ideal gas (γ=1.5\gamma=1.5) is changed adiabatically from 55 litres to 44 litres. The ratio of initial pressure to final…EasySingle correct
  10. 9 Apr 2024, Shift 2 · Q36A real gas within a closed chamber at 27∘C27^\circ C undergoes the cyclic process as shown in figure. The gas obeys PV3=RTPV^3=RT equation for…HardSingle correctHas a figure
  11. 1 Feb 2024, Shift 1 · Q38The pressure and volume of an ideal gas are related as PV32=KPV^{\frac{3}{2}} = K (Constant). The work done when the gas is taken from state A…MediumSingle correct
  12. 1 Feb 2024, Shift 2 · Q38A diatomic gas (γ=1.4\gamma = 1.4) does 200 J of work when it is expanded isobarically. The heat given to the gas in the process is :EasySingle correct
  13. 27 Jan 2024, Shift 1 · Q380.08 kg air is heated at constant volume through 5°C. The specific heat of air at constant volume is 0.17 kcal/kg°C and J = 4.18…EasySingle correct
  14. 30 Jan 2024, Shift 1 · Q38Two thermodynamical processes are shown in the figure. The molar heat capacity for process A and B are CAC_A and CBC_B. The molar heat…HardDiagram basedHas a figure
  15. 30 Jan 2024, Shift 2 · Q38Choose the correct statement for processes AA & BB shown in figure.MediumSingle correctHas a figure
  16. 30 Jan 2024, Shift 2 · Q39If three moles of monoatomic gas (γ=53)\left(\gamma = \frac{5}{3}\right) is mixed with two moles of a diatomic gas…MediumSingle correct
  17. 31 Jan 2024, Shift 2 · Q39A gas mixture consists of 8 moles of argon and 6 moles of oxygen at temperature T. Neglecting all vibrational modes, the total internal…EasySingle correct

JEE Main 202310 questions

  1. 6 Apr 2023, Shift 1 · Q44A source supplies heat to a system at the rate of 1000 W. If the system performs work at a rate of 200 W. The rate at which internal…EasySingle correct
  2. 8 Apr 2023, Shift 1 · Q33Given below are two statements: Statement I: If heat is added to a system, its temperature must increase. Statement II: If positive work…MediumTwo statements
  3. 8 Apr 2023, Shift 2 · Q34Carnot Efficiency Limit · Easy · Single correct
  4. 10 Apr 2023, Shift 1 · Q33Adiabatic Process Analysis · Medium · Single correct
  5. 10 Apr 2023, Shift 2 · Q34Adiabatic Process Analysis · Easy · Single correct
  6. 11 Apr 2023, Shift 1 · Q44First Law in Phase Transitions · Medium · Single correct
  7. 11 Apr 2023, Shift 2 · Q34Isothermal Process Analysis · Easy · Single correct
  8. 12 Apr 2023, Shift 1 · Q38Carnot Efficiency Limit · Medium · Other
  9. 13 Apr 2023, Shift 2 · Q38Adiabatic P-V Relation · Easy · Single correct
  10. 15 Apr 2023, Shift 1 · Q33Cyclic Process Work · Easy · Diagram based · has a figure

JEE Main 202223 questions

  1. 25 Jul 2022, Shift 1 · Q37Adiabatic Process Analysis · Medium · Single correct
  2. 25 Jul 2022, Shift 2 · Q45Carnot Efficiency Limit · Easy · Single correct
  3. 26 Jul 2022, Shift 1 · Q43Internal Energy Calculation · Easy · Single correct
  4. 26 Jul 2022, Shift 1 · Q44Adiabatic Process Analysis · Easy · Single correct
  5. 27 Jul 2022, Shift 2 · Q38Carnot Engines in Series · Easy · Diagram based · has a figure
  6. 28 Jul 2022, Shift 1 · Q37Carnot Efficiency Limit · Medium · Single correct
  7. 28 Jul 2022, Shift 2 · Q24Degrees of Freedom · Easy · Numerical value
  8. 29 Jul 2022, Shift 1 · Q53Adiabatic T-V and P-T Relations · Medium · Numerical value
  9. 29 Jul 2022, Shift 2 · Q47Work Done from P-V Graph Area · Easy · Diagram based · has a figure
  10. 30 Jul 2022, Shift 2 · Q7Carnot Efficiency Limit · Easy · Single correct
  11. 24 Jun 2022, Shift 1 · Q47Carnot Efficiency Limit · Medium · Single correct
  12. 24 Jun 2022, Shift 2 · Q35Carnot Efficiency Limit · Easy · Single correct
  13. 24 Jun 2022, Shift 2 · Q59Molar Heat Capacity in Polytropic Processes · Medium · Numerical value
  14. 26 Jun 2022, Shift 1 · Q37Carnot Efficiency Limit · Easy · Single correct
  15. 26 Jun 2022, Shift 2 · Q55Carnot Engine Efficiency · Medium · Numerical value
  16. 27 Jun 2022, Shift 1 · Q51Carnot Engine Efficiency · Easy · Numerical value
  17. 27 Jun 2022, Shift 2 · Q53Heat in Isochoric and Isobaric Processes · Easy · Numerical value
  18. 28 Jun 2022, Shift 1 · Q37Adiabatic Process Analysis · Medium · Two statements
  19. 28 Jun 2022, Shift 2 · Q38First Law in Cyclic Processes · Medium · Diagram based · has a figure
  20. 29 Jun 2022, Shift 1 · Q35Heat in Isochoric and Isobaric Processes · Easy · Single correct
  21. 29 Jun 2022, Shift 1 · Q56Carnot Heat-Temperature Ratio · Easy · Numerical value
  22. 29 Jun 2022, Shift 2 · Q38Work Comparison in Gas Expansions · Easy · Single correct
  23. 30 Jun 2022, Shift 1 · Q41Adiabatic Work Evaluation · Medium · Single correct

JEE Main 202130 questions

  1. 3 Aug 2021, Shift 1 · Q5Carnot Efficiency Limit · Easy · Single correct
  2. 3 Aug 2021, Shift 2 · Q3Internal Energy Calculation · Medium · Single correct
  3. 4 Aug 2021, Shift 1 · Q25First Law in Phase Transitions · Easy · Numerical value
  4. 4 Aug 2021, Shift 2 · Q13Second Law Statements · Medium · Two statements
  5. 26 Aug 2021, Shift 1 · Q4First Law Energy Balance · Easy · Single correct
  6. 26 Aug 2021, Shift 2 · Q14Refrigerator COP · Easy · Single correct
  7. 27 Aug 2021, Shift 1 · Q7Volume Expansion Coefficient of Ideal Gas · Medium · Single correct
  8. 27 Aug 2021, Shift 2 · Q7Specific Heat Capacity · Easy · Single correct
  9. 27 Aug 2021, Shift 2 · Q26Carnot Efficiency Limit · Easy · Numerical value
  10. 31 Aug 2021, Shift 1 · Q14Open the question · Hard · Single correct
  11. 31 Aug 2021, Shift 1 · Q15Carnot Efficiency Limit · Medium · Single correct
  12. 31 Aug 2021, Shift 2 · Q22Adiabatic Process Analysis · Medium · Numerical value
  13. 24 Feb 2021, Shift 1 · Q9Cyclic Process Work · Medium · Diagram based · has a figure
  14. 24 Feb 2021, Shift 1 · Q10Isothermal Process Analysis · Easy · Match the list
  15. 24 Feb 2021, Shift 2 · Q5Cyclic Process Work · Hard · Diagram based · has a figure
  16. 25 Feb 2021, Shift 1 · Q18Heat in Isochoric and Isobaric Processes · Easy · Single correct
  17. 25 Feb 2021, Shift 1 · Q29Polytropic Process Analysis · Medium · Numerical value
  18. 25 Feb 2021, Shift 2 · Q5Polytropic Process Analysis · Easy · Diagram based · has a figure
  19. 25 Feb 2021, Shift 2 · Q25Carnot Efficiency Limit · Medium · Numerical value
  20. 26 Feb 2021, Shift 2 · Q23Polytropic Process Analysis · Medium · Numerical value
  21. 26 Feb 2021, Shift 2 · Q27Molar Heat Capacity in Polytropic Processes · Medium · Numerical value
  22. 25 Jul 2021, Shift 1 · Q13Open the question · Hard · Single correct
  23. 25 Jul 2021, Shift 1 · Q20Adiabatic T-V and P-T Relations · Easy · Single correct
  24. 25 Jul 2021, Shift 2 · Q9Carnot Efficiency Limit · Medium · Single correct
  25. 16 Mar 2021, Shift 2 · Q26Carnot Efficiency Limit · Easy · Numerical value
  26. 17 Mar 2021, Shift 1 · Q3Carnot Efficiency Limit · Easy · Single correct
  27. 17 Mar 2021, Shift 2 · Q19Indicator Diagram Conversions · Medium · Diagram based · has a figure
  28. 18 Mar 2021, Shift 1 · Q4Adiabatic Process Analysis · Medium · Single correct · has a figure
  29. 18 Mar 2021, Shift 2 · Q9Adiabatic Process Analysis · Easy · Single correct
  30. 18 Mar 2021, Shift 2 · Q11Extensive Nature of Entropy · Easy · Single correct

JEE Main 202012 questions

  1. 8 Jan 2020, Shift 1 · Q8Indicator Diagram Conversions · Medium · Diagram based · has a figure
  2. 8 Jan 2020, Shift 2 · Q7Efficiency and COP Conversion · Easy · Single correct
  3. 9 Jan 2020, Shift 1 · Q7Indicator Diagram Conversions · Medium · Diagram based · has a figure
  4. 9 Jan 2020, Shift 2 · Q21Adiabatic T-V and P-T Relations · Medium · Numerical value
  5. 2 Sep 2020, Shift 1 · Q22Adiabatic T-V and P-T Relations · Medium · Numerical value
  6. 2 Sep 2020, Shift 2 · Q8Heat Engine Efficiency · Easy · Single correct
  7. 3 Sep 2020, Shift 1 · Q7Irreversible Adiabatic Processes · Easy · Single correct
  8. 3 Sep 2020, Shift 2 · Q8Gamma and Degrees of Freedom · Medium · Single correct
  9. 3 Sep 2020, Shift 2 · Q23Carnot Refrigerator COP via Temperatures · Medium · Numerical value
  10. 4 Sep 2020, Shift 2 · Q9Adiabatic Process Analysis · Easy · Match the list
  11. 5 Sep 2020, Shift 1 · Q8State vs. Path Functions · Medium · Diagram based · has a figure
  12. 6 Sep 2020, Shift 2 · Q22Non-Carnot Cycle Efficiency · Medium · Numerical value · has a figure

JEE Main 20171 question

  1. 2 Apr 2017 (offline) · Q10Mayer's Relation (Cp and Cv) · Easy · Single correct

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 11

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