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Sunday, 25 October

JEE Main · Physics · Class 12

Alternating Current: JEE Main previous year questions

108 questions in 79 of the 108 JEE Main shifts Lumi analysed, asked in 7 of 8 years. Here is what this chapter tests and how.

Study this chapter
Questions
108
in 79 of 108 shifts · 7 of 8 years
Average a shift
0.7
of 25 Physics · 0.8 since 2024 0.2
Typical range
0.3–1.0
questions a shift; fewest 0.0, most 1.2
Weighted estimate
0.8
model, recent years count more · about 3.1 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 Alternating Current

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
108in 79 of 108 shifts
Study plan gives it
13 hover 12 months; 10 h over 6
Study this chapter →

Ideas asked most often

  1. Impedance Triangle Construction9×
  2. Power Factor from Phasors9×
  3. Resonant Frequency Calculation9×
  4. Phase Relations in RLC8×
  5. Impedance at Resonance5×

132 of the 178 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, 19% 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

Alternating Current at a glance

  1. 01

    81%

    of its 32 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

    74%

    of the 178 ideas in Lumi's map of the chapter have not been asked or touched on in the shifts analysed.

  3. 03

    38%

    of its questions asked for a numerical answer, 1.3 times the Physics average.

  4. 04

    5%

    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.

0240’170.3’201’211.2’220.6’231’240.6’250.8’26

Raw count: 2017: 0 in 1 shift · 2020: 4 in 12 shifts · 2021: 28 in 24 shifts · 2022: 34 in 24 shifts · 2023: 8 in 12 shifts · 2024: 22 in 18 shifts · 2025: 5 in 8 shifts · 2026: 7 in 9 shifts.

Kind of question

SHARE OF QUESTIONS
  • Numerical answer38%
  • Calculation26%
  • Conceptual9%
  • Multi-step7%
  • Diagram based7%
  • Two statements5%
  • Match the list4%
  • Application2%
  • Recall, single correct1%
  • Data or graph1%

Most common asks: inductance from given phase angles (1); resonant frequency of series lcr (1); identify circuit with wattless current (1).

Profile

This chapter in numbers

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

Rank, all JEE chapters
#52
of 70 by weighted estimate
Rank in Physics
#16
of 28 chapters
Share of Physics
2.7%
of its questions, all shifts analysed
Busiest year
2022
1.2 questions a shift
Year to year
Swings a lot
varies by about 0.4 questions a shift
Long-run direction
+0.08
questions a shift, per year
Easy questions
53%
5% rated hard
Numerical answer
38%
1.3× the Physics rate
With a figure
21%
graph, diagram or structure
Study time
13 h
10 h on a 6-month plan
Marks per study hour
0.23
#40 of 70 chapters
Foundation for others
84%
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).

  • 2017
  • 20204
  • 202128
  • 202234
  • 20238
  • 202422
  • 20255
  • 20267
  • Easy
  • Medium
  • Hard

What it asks you to do

SHARE OF QUESTIONS
  • Calculation48%
  • Multi-step26%
  • Conceptual15%
  • Application5%
  • Recall3%
  • Data or graph2%
  • Diagram reading2%

Coverage

How much of the chapter JEE Main has used

We split the chapter into 178 ideas. In the 108 shifts analysed, JEE Main built a question around 36 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
36
Touched on in a question
10
Never asked
132

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. 10 questions had no close topic in Lumi's map and count for the chapter only.

’17’20’21’22’23’24’25’26
013+questions in that year’s analysed shifts, shaded per shift
  • Phasor Diagrams

    As a topic: 43 questions in 7 of 8 years, most often single correct, 35% numerical answer.

  • LCR Resonance

    As a topic: 35 questions in 5 of 8 years, most often numerical value, 51% numerical answer.

  • RMS and Peak Values

    As a topic: 14 questions in 4 of 8 years, most often single correct, 21% numerical answer.

  • Inductance

    As a topic: 31 questions in 7 of 8 years, most often numerical value, 45% 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.

  • Open43 · 40%471221224

    13 ideas inside

    • OpenRepeated9 · 21%323
    • OpenRepeated9 · 21%223
    • OpenRepeated8 · 19%222
    • OpenRepeated4 · 9%2
    • OpenRepeated3 · 7%2
    • OpenRepeated2 · 5%
    • OpenRepeated2 · 5%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
    • Open1 · 2%
  • Open35 · 32%111355
  • Open14 · 13%5423
  • Open4 · 4%2
  • 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, 38 different ideas were tested; 20 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 108 Alternating Current 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 20267 questions

  1. 2 Apr 2026, Shift 2 · Q42The figure given below shows an LCR series circuit with two switches S1S_1 and S2S_2. When switch S1S_1 is closed keeping S2S_2 open, the…HardSingle correctHas a figure
  2. 4 Apr 2026, Shift 1 · Q42Consider a circuit consisting of a capacitor (20 μ20\ \muF), resistor (100 Ω100\ \Omega) and two identical diodes as shown in figure. The…MediumDiagram basedHas a figure
  3. 4 Apr 2026, Shift 1 · Q50An inductor of 1010 mH, capacitor of 0.1 μ0.1\ \muF and a resistor of 100 Ω100\ \Omega are connected in series across an a.ca.c power supply…MediumNumerical value
  4. 5 Apr 2026, Shift 1 · Q44An a.c. source of angular frequency ω\omega is connected across a resistor RR and a capacitor CC in series. The current is observed as…MediumSingle correct
  5. 5 Apr 2026, Shift 2 · Q48A series LCR circuit with R=20 ΩR=20\ \Omega, L=1.6L=1.6 H and C=40 μFC=40\ \mu\mathrm{F} is connected to a variable frequency a.c. source. The…EasyNumerical value
  6. 6 Apr 2026, Shift 1 · Q43An inductor of inductance 10 mH having resistance of 100 Ω\Omega is connected to battery of E.M.F. 1.0 V through a switch as shown in the…MediumSingle correctHas a figure
  7. 6 Apr 2026, Shift 1 · Q45A LCR series circuit driven with Erms=90E_{rms}=90 V at frequency fd=30f_d=30 Hz has resistance R=80 ΩR=80\ \Omega, an inductance with inductive…EasySingle correct

JEE Main 20255 questions

  1. 3 Apr 2025, Shift 2 · Q37An electric bulb rated as 100W-220V is connected to an ac source of rms voltage 220V. The peak value of current through the bulb is :EasySingle correct
  2. 4 Apr 2025, Shift 2 · Q48An inductor of self inductance 1 H is connected in series with a resistor of 100 π100\,\pi ohm and an ac supply of 100 π100\,\pi volt, 50 Hz.…MediumNumerical value
  3. 7 Apr 2025, Shift 1 · Q35An ac current is represented as i=52+10cos⁡(650πt+π6)i = 5\sqrt{2} + 10\cos\left(650\pi t + \frac{\pi}{6}\right) Amp The r.m.s value of the current isEasySingle correct
  4. 7 Apr 2025, Shift 1 · Q49For ac circuit shown in figure, R = 100 kΩ\Omega and C = 100 pF and the phase difference between Vin\mathrm{V_{in}} and…HardNumerical valueHas a figure
  5. 7 Apr 2025, Shift 2 · Q48An inductor of reactance 100 Ω100\ \Omega, a capacitor of reactance 50 Ω50\ \Omega, and a resistor of resistance 50 Ω50\ \Omega are connected in…EasyNumerical value

JEE Main 202422 questions

  1. 4 Apr 2024, Shift 1 · Q43In an ac circuit, the instantaneous current is zero, when the instantaneous voltage is maximum. In this case, the source may be connected…MediumOther
  2. 4 Apr 2024, Shift 1 · Q58A alternating current at any instant is given by i=[6+56sin⁡(100πt+π/3)]i = \left[6 + \sqrt{56}\sin(100\pi t + \pi/3)\right] A. The rms value of the current is…MediumNumerical value
  3. 4 Apr 2024, Shift 2 · Q44Match List I with List II LIST I | LIST II A. Purely capacitive circuit | I. [figure: phasor diagram, II along the vertical axis (up) and…MediumMatch the listHas a figure
  4. 5 Apr 2024, Shift 1 · Q57An ac source is connected in given series LCR circuit. The rms potential difference across the capacitor of 20 μF20\ \mu\mathrm{F} is…MediumNumerical valueHas a figure
  5. 5 Apr 2024, Shift 2 · Q41A series LCR circuit is subjected to an ac signal of 200 V, 50 Hz. If the voltage across the inductor (L=10 mH) is 31.4 V, then the…EasySingle correct
  6. 6 Apr 2024, Shift 1 · Q44Given below are two statements : Statement I : In an LCR series circuit, current is maximum at resonance. Statement II : Current in a…EasyTwo statements
  7. 6 Apr 2024, Shift 1 · Q55When a dcdc voltage of 100V is applied to an inductor, a dcdc current of 5A flows through it. When an acac voltage of 200V peak value is…MediumNumerical value
  8. 6 Apr 2024, Shift 2 · Q59For a given series LCR circuit it is found that maximum current is drawn when value of variable capacitance is 2.5 nF. If resistance of…EasyNumerical value
  9. 8 Apr 2024, Shift 1 · Q50A LCR circuit is at resonance for a capacitor C, inductance L and resistance R. Now the value of resistance is halved keeping all other…EasySingle correct
  10. 8 Apr 2024, Shift 2 · Q43A coil of negligible resistance is connected in series with 90 Ω90\ \Omega resistor across 120120 V, 6060 Hz supply. A voltmeter reads 3636 V…MediumSingle correct
  11. 8 Apr 2024, Shift 2 · Q58An alternating emf E=1102 sin⁡100tE = 110\sqrt{2}\ \sin 100t volt is applied to a capacitor of 2 μF2\,\mu\mathrm{F}, the rms value of current in the…EasyNumerical value
  12. 9 Apr 2024, Shift 1 · Q43A bulb and a capacitor are connected in series across an ac supply. A dielectric is then placed between the plates of the capacitor. The…MediumSingle correct
  13. 9 Apr 2024, Shift 1 · Q58When a coil is connected across a 2020 V dc supply, it draws a current of 55 A. When it is connected across 2020 V, 5050 Hz ac supply, it…MediumNumerical value
  14. 9 Apr 2024, Shift 2 · Q53A capacitor of reactance 43 Ω4\sqrt{3}\ \Omega and a resistor of resistance 4 Ω4\ \Omega are connected in series with an ac source of peak…MediumNumerical value
  15. 1 Feb 2024, Shift 1 · Q43In series LCR circuit, the capacitance is changed from C to 4C. To keep the resonance frequency unchanged, the new inductance should be :EasySingle correct
  16. 1 Feb 2024, Shift 2 · Q43A transformer has an efficiency of 80% and works at 10 V and 4 kW. If the secondary voltage is 240 V, then the current in the secondary…EasySingle correct
  17. 29 Jan 2024, Shift 1 · Q43A capacitor of capacitance 100 μ100\ \muF is charged to a potential of 12 V and connected to a 6.4 mH inductor to produce oscillations. The…EasySingle correct
  18. 30 Jan 2024, Shift 1 · Q43A series L.R circuit connected with an ac source E=(25sin⁡1000 t)E = (25\sin 1000\,t) V has a power factor of 12\frac{1}{\sqrt{2}}. If the source of emf…MediumSingle correct
  19. 30 Jan 2024, Shift 1 · Q50Primary coil of a transformer is connected to 220 V ac. Primary and secondary turns of the transforms are 100 and 10 respectively.…EasyDiagram basedHas a figure
  20. 30 Jan 2024, Shift 2 · Q43An alternating voltage V(t)=220sin⁡100πtV(t) = 220\sin 100\pi t volt is applied to a purely resistive load of 50 Ω50\ \Omega. The time taken for the…MediumSingle correct
  21. 30 Jan 2024, Shift 2 · Q58A power transmission line feeds input power at 2.3kV2.3kV to a step down transformer with its primary winding having 3000 turns. The output…EasyNumerical value
  22. 31 Jan 2024, Shift 2 · Q43An AC voltage V=20sin⁡200πtV=20\sin 200\pi t is applied to a series LCR circuit which drives a current I=10sin⁡(200πt+π3)I=10\sin\left(200\pi t+\frac{\pi}{3}\right).…EasySingle correct

JEE Main 20238 questions

  1. 6 Apr 2023, Shift 1 · Q54An ideal transformer with purely resistive load operates at 12 kV on the primary side. It supplies electrical energy to a number of nearby…MediumNumerical value
  2. 6 Apr 2023, Shift 2 · Q47A capacitor of capacitance 150.0 μ\muF is connected to an alternating source of emf given by E=36sin⁡(120πt)E=36\sin(120\pi t) V. The maximum value of…EasySingle correct
  3. 8 Apr 2023, Shift 1 · Q57An oscillating LC circuit consists of a 75 mH75\ \mathrm{mH} inductor and a 1.2 μF1.2\ \mu\mathrm{F} capacitor. If the maximum charge to the…EasyNumerical value
  4. 8 Apr 2023, Shift 2 · Q58A series combination of resistor of resistance 100 Ω\Omega, inductor of inductance 1 H and capacitor of capacitance 6.25 μ\muF is…EasyNumerical value
  5. 10 Apr 2023, Shift 1 · Q45Given below are two statements : Statement I : Maximum power is dissipated in a circuit containing an inductor, a capacitor and a resistor…EasyTwo statements
  6. 11 Apr 2023, Shift 1 · Q36As per the given graph, choose the correct representation for curve A and curve B. {Where XCX_C = reactance of pure capacitive circuit…EasyDiagram basedHas a figure
  7. 12 Apr 2023, Shift 1 · Q35Power Factor at Resonance · Easy · Two statements
  8. 13 Apr 2023, Shift 2 · Q44Phase Relations in RLC · Medium · Two statements

JEE Main 202234 questions

  1. 25 Jul 2022, Shift 1 · Q42Resonant Frequency Calculation · Easy · Single correct
  2. 25 Jul 2022, Shift 1 · Q44Open the question · Medium · Single correct
  3. 25 Jul 2022, Shift 2 · Q40Resonance Condition · Easy · Single correct
  4. 26 Jul 2022, Shift 1 · Q37Power Factor from Phasors · Easy · Single correct
  5. 26 Jul 2022, Shift 1 · Q57High-Frequency Blocking in Series LCR · Hard · Numerical value · has a figure
  6. 27 Jul 2022, Shift 1 · Q44Ratio of AC to DC Heat Dissipation · Easy · Single correct
  7. 27 Jul 2022, Shift 1 · Q54RC Series Phasor Construction · Medium · Numerical value
  8. 27 Jul 2022, Shift 2 · Q44Impedance Triangle Construction · Medium · Single correct
  9. 28 Jul 2022, Shift 1 · Q44Phase Relations in RLC · Medium · Single correct
  10. 28 Jul 2022, Shift 1 · Q54Half-Power Frequencies · Medium · Numerical value
  11. 28 Jul 2022, Shift 2 · Q14Open the question · Medium · Single correct
  12. 29 Jul 2022, Shift 1 · Q43AC Measuring Instruments · Easy · Single correct
  13. 29 Jul 2022, Shift 2 · Q38Series Phasor Addition · Medium · Single correct
  14. 29 Jul 2022, Shift 2 · Q60LC Energy Oscillation at Resonance · Easy · Numerical value
  15. 30 Jul 2022, Shift 2 · Q12Power Factor from Phasors · Easy · Single correct
  16. 30 Jul 2022, Shift 2 · Q23Impedance at Resonance · Easy · Numerical value
  17. 24 Jun 2022, Shift 1 · Q41Time from Peak to RMS · Easy · Single correct
  18. 24 Jun 2022, Shift 1 · Q54Open the question · Medium · Numerical value · has a figure
  19. 24 Jun 2022, Shift 2 · Q40Series LC Phasor Subtraction · Medium · Two statements
  20. 25 Jun 2022, Shift 1 · Q39Open the question · Easy · Match the list
  21. 25 Jun 2022, Shift 1 · Q41Wattless (Reactive) Current Component · Easy · Single correct
  22. 25 Jun 2022, Shift 2 · Q42Impedance Triangle Construction · Medium · Single correct
  23. 25 Jun 2022, Shift 2 · Q59Impedance at Resonance · Easy · Numerical value · has a figure
  24. 26 Jun 2022, Shift 1 · Q59Parallel Resonance (Anti-resonance) · Medium · Numerical value · has a figure
  25. 27 Jun 2022, Shift 1 · Q41Time from Zero to Peak · Easy · Single correct
  26. 27 Jun 2022, Shift 1 · Q52Purely Resistive Phasor Diagram · Medium · Numerical value · has a figure
  27. 27 Jun 2022, Shift 2 · Q44Dimensional Analysis of Inductance · Easy · Single correct
  28. 28 Jun 2022, Shift 1 · Q54Impedance Triangle Construction · Medium · Numerical value · has a figure
  29. 28 Jun 2022, Shift 1 · Q60Resonant Frequency Calculation · Easy · Numerical value
  30. 28 Jun 2022, Shift 2 · Q54Series Phasor Addition · Medium · Numerical value · has a figure
  31. 29 Jun 2022, Shift 1 · Q40Series LCR Capacitive Below Resonance · Easy · Other · has a figure
  32. 29 Jun 2022, Shift 2 · Q60Resonant Frequency Calculation · Easy · Numerical value
  33. 30 Jun 2022, Shift 1 · Q46Q-Factor Formula in LCR · Medium · Single correct
  34. 30 Jun 2022, Shift 1 · Q57Power Factor at Resonance · Medium · Numerical value

JEE Main 202128 questions

  1. 3 Aug 2021, Shift 1 · Q24Energy Stored in Inductors · Medium · Numerical value
  2. 4 Aug 2021, Shift 2 · Q5Real Inductor (Choke Coil) Phasors · Medium · Single correct
  3. 26 Aug 2021, Shift 1 · Q10Resonance Condition · Easy · Single correct
  4. 27 Aug 2021, Shift 1 · Q28RMS of DC and AC Superposition · Easy · Numerical value
  5. 27 Aug 2021, Shift 2 · Q22Power Factor from Phasors · Medium · Numerical value
  6. 31 Aug 2021, Shift 1 · Q8Impedance at Resonance · Easy · Single correct
  7. 31 Aug 2021, Shift 2 · Q28Frequency Variation in RC Phasors · Hard · Numerical value · has a figure
  8. 24 Feb 2021, Shift 1 · Q26Quality Factor Definition · Easy · Numerical value
  9. 24 Feb 2021, Shift 1 · Q30Open the question · Easy · Numerical value
  10. 24 Feb 2021, Shift 2 · Q11Self-Inductance and Back EMF · Medium · Diagram based · has a figure
  11. 24 Feb 2021, Shift 2 · Q28Power Factor at Resonance · Easy · Numerical value
  12. 25 Feb 2021, Shift 1 · Q17Series Phasor Addition · Hard · Diagram based · has a figure
  13. 25 Feb 2021, Shift 1 · Q27Resonant Frequency Calculation · Easy · Numerical value
  14. 25 Feb 2021, Shift 2 · Q12Impedance at Resonance · Medium · Single correct
  15. 26 Feb 2021, Shift 1 · Q14RMS Calculation via Integration · Easy · Single correct
  16. 26 Feb 2021, Shift 1 · Q30Q-Factor Formula in LCR · Easy · Numerical value
  17. 26 Feb 2021, Shift 2 · Q18Resonant Frequency Calculation · Medium · Diagram based · has a figure
  18. 22 Jul 2021, Shift 2 · Q4Phase Relations in RLC · Easy · Diagram based · has a figure
  19. 22 Jul 2021, Shift 2 · Q16Phase Angle Frequency Sweep · Easy · Match the list
  20. 25 Jul 2021, Shift 2 · Q15Time from Peak to RMS · Easy · Single correct
  21. 25 Jul 2021, Shift 2 · Q25Resonant Frequency Calculation · Medium · Numerical value · has a figure
  22. 16 Mar 2021, Shift 2 · Q11Open the question · Easy · Diagram based · has a figure
  23. 17 Mar 2021, Shift 1 · Q7AC Measuring Instruments · Easy · Single correct
  24. 17 Mar 2021, Shift 2 · Q7Phase Relations in RLC · Easy · Match the list
  25. 17 Mar 2021, Shift 2 · Q8Open the question · Easy · Single correct
  26. 18 Mar 2021, Shift 1 · Q6Time from Peak to RMS · Easy · Single correct
  27. 18 Mar 2021, Shift 1 · Q15Resistance Effect on Resonance Curve · Medium · Single correct
  28. 18 Mar 2021, Shift 2 · Q13Power Factor from Phasors · Easy · Single correct

JEE Main 20204 questions

  1. 9 Jan 2020, Shift 2 · Q15Phase Relations in RLC · Medium · Single correct
  2. 2 Sep 2020, Shift 2 · Q14Real Inductor (Choke Coil) Phasors · Medium · Single correct
  3. 3 Sep 2020, Shift 1 · Q15Impedance Triangle Construction · Medium · Single correct
  4. 6 Sep 2020, Shift 2 · Q23Power Factor from Phasors · Medium · Numerical value

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