JEE Main · Physics · Alternating Current
LCR Resonance: JEE Main previous year questions
35 questions in the 108 JEE Main shifts Lumi analysed, in 5 of 8 years. Pattern: Asked most years. 6 came in 2024–26. Here is how it is asked and which ideas come back.
- Questions
- 35
- in 34 of 108 shifts
- Years asked
- 5/8
- last asked 2026
- Weighted estimate
- 0.2
- model; history: 0.2 a shift on average, typically 0.0–0.4
Key findings
- 01
Asked in 5 of 8 years with analysed shifts and in 34 of 108 shifts: 35 questions, #100 of 196 topics. The years that asked it were 1.2 apart on average.
- 02
51% of its questions since 2020 tested an idea no earlier year had asked; 12 repeated an idea from the year before.
- 03
The most repeated idea is Resonant Frequency Calculation, asked 9 times in 9 shifts (2021, 2022, 2024, 2026), most often as “reactance at resonance from lcr values”.
- 04
JEE Main has asked 15 of the 62 ideas in this topic; 44 have never been asked, directly or inside another question.
- 05
Mostly asked as numerical value (51%); 51% need a numerical answer, 74% are easy and 3% hard.
- 06
The skill tested most is calculation (51%), then conceptual (23%).
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.
Raw count: 2017: 0 in 1 shift · 2020: 0 in 12 shifts · 2021: 11 in 24 shifts · 2022: 13 in 24 shifts · 2023: 5 in 12 shifts · 2024: 5 in 18 shifts · 2025: 0 in 8 shifts · 2026: 1 in 9 shifts.
- Up to 2023
- 0.2
- a shift, of 25
- Since 2024
- 0.1
- -0.1
- Usual gap
- 1.2 yrs
- between years asking it
- Shifts with it
- 34/108
- 31% of analysed shifts
How it is asked
Difficulty, format and skill
Across all 35 questions on LCR Resonance since 2017.
Difficulty
QUESTIONS- Easy26 · 74%
- Medium8 · 23%
- Hard1 · 3%
Format
SHARE- Numerical value · 18 Q51%
- Single correct · 10 Q29%
- Two statements · 3 Q9%
- Diagram based · 2 Q6%
- Other · 1 Q3%
- Match the list · 1 Q3%
Skill tested
SHARE- Calculation · 18 Q51%
- Conceptual · 8 Q23%
- Multi-step · 4 Q11%
- Data or graph · 2 Q6%
- Application · 2 Q6%
- Recall · 1 Q3%
Repeats
New idea, or one asked before?
Each column is a year. Blue questions tested an idea no earlier year had asked; navy ones went back to an idea from an earlier year. 2017 is the first year, so everything in it counts as new. Heights are question counts, and Lumi analysed 1 to 24 shifts a year, so compare the split inside a column rather than heights across years.
- Idea asked for the first time
- Idea asked in an earlier year
Coverage of the topic
JEE Main has asked 15 of the 62 ideas in this topic. 44 have never been asked yet.
- Asked directly15 · 24%
- Touched inside another question3 · 5%
- Never asked44 · 71%
Ideas come from Lumi’s JEE syllabus map. A never-asked idea is not a safe skip: across all of JEE Main, 22% of questions since 2024 tested an idea no earlier year had asked.
Drill down
Idea, year, question
Every idea JEE Main tested in this topic, with its eight years. Open one to read the questions.
- 5 Apr ’26 S2 · Q48A series LCR circuit with , H and is connected to a variable frequency a.c. source. The…
easyNumerical value
- 6 Apr ’24 S2 · 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
- 1 Feb ’24 S1 · 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
- 25 Jul ’22 S1 · Q42To increase the resonant frequency in series LCR circuit,
easySingle correctAsked the year before
- 28 Jun ’22 S1 · Q60A telegraph line of length 100 km has a capacity of 0.01 F/km and it carries an alternating current at 0.5 kilo cycle per second. If…
easyNumerical valueAsked the year before
- 29 Jun ’22 S2 · Q60An inductor of 0.5 mH, a capacitor of 200 μF and a resistor of 2 Ω are connected in series with a 220 ac source. If the current is in…
easyNumerical valueAsked the year before
- 25 Feb ’21 S1 · Q27A transmitting station releases waves of wavelength 960 m. A capacitor of F is used in the resonant circuit. The self…
easyNumerical valueNew idea
- 26 Feb ’21 S2 · Q18Read the question
mediumDiagram basedNew idea
- 25 Jul ’21 S2 · Q25Read the question
mediumNumerical valueNew idea
- 5 Apr ’26 S2 · Q48
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
Every idea inside this topic
15 different ideas were tested; 7 came more than once.
reactance at resonance from lcr values
Numerical value · 9 shifts · 6 numericalstatement i/ii on lcr circuit
Numerical value · 5 shifts · 2 numericalstatement i/ii on power in series lcr circuit
Numerical value · 4 shifts · 2 numericalpeak current in lc oscillation
Numerical value · 3 shifts · 2 numericaleffect of resistance on series lcr resonance
Single correct · 2 shiftseffect on resonant frequency and quality factor
Numerical value · 2 shifts · 1 numericalidentify principle behind everyday device
Single correct · 2 shiftsgraph interpretation of reactance vs frequency
Diagram based · 1 shiftquality factor of series lcr
Numerical value · 1 shift · 1 numericalinductance from half-power frequencies
Numerical value · 1 shift · 1 numericaleffective current in rlc network at limiting frequency
Numerical value · 1 shift · 1 numericalcurrent in series resistor at parallel lc resonance
Numerical value · 1 shift · 1 numericaltrue statement selection on lcr resonance
Other · 1 shiftmatch list on lcr circuit conditions
Match the list · 1 shiftquality factor of resonant circuit
Numerical value · 1 shift · 1 numerical
| Idea | Years asked | Times | Shifts | Format | Numerical |
|---|---|---|---|---|---|
| Resonant Frequency Calculationreactance at resonance from lcr values | 9 | 9 | Numerical valueCalculation | 6 | |
| Impedance at Resonancestatement i/ii on lcr circuit | 5 | 5 | Numerical valueCalculation | 2 | |
| Power Factor at Resonancestatement i/ii on power in series lcr circuit | 4 | 4 | Numerical valueCalculation | 2 | |
| LC Energy Oscillation at Resonancepeak current in lc oscillation | 3 | 3 | Numerical valueCalculation | 2 | |
| Resistance Effect on Resonance Curveeffect of resistance on series lcr resonance | 2 | 2 | Single correctConceptual | – | |
| Q-Factor Formula in LCReffect on resonant frequency and quality factor | 2 | 2 | Numerical valueApplication | 1 | |
| Resonance Conditionidentify principle behind everyday device | 2 | 2 | Single correctCalculation | – | |
| Impedance vs Frequency Curvegraph interpretation of reactance vs frequency | 1 | 1 | Diagram basedData or graph | – | |
| Q-Factor Formula in L, C, Rquality factor of series lcr | 1 | 1 | Numerical valueCalculation | 1 | |
| Half-Power Frequenciesinductance from half-power frequencies | 1 | 1 | Numerical valueCalculation | 1 | |
| High-Frequency Blocking in Series LCReffective current in rlc network at limiting frequency | 1 | 1 | Numerical valueMulti-step | 1 | |
| Parallel Resonance (Anti-resonance)current in series resistor at parallel lc resonance | 1 | 1 | Numerical valueApplication | 1 | |
| Series LCR Capacitive Below Resonancetrue statement selection on lcr resonance | 1 | 1 | OtherData or graph | – | |
| Phase Angle Frequency Sweepmatch list on lcr circuit conditions | 1 | 1 | Match the listConceptual | – | |
| Quality Factor Definitionquality factor of resonant circuit | 1 | 1 | Numerical valueCalculation | 1 |
Times and shifts count every analysed shift. Across JEE Main, 78% of questions since 2024 went back to an idea an earlier year had asked; the rest were new. All repeated ideas
Every question
LCR Resonance questions, year by year
The opening words of each question as it appeared in the official paper, with the idea it tested. Open one for its options and the official answer.
JEE Main 20261 question in 1 shift
- 5 Apr, Shift 2Q48A series LCR circuit with , H and is connected to a variable frequency a.c. source. The…
Idea: Resonant Frequency Calculation
EasyNumerical value
JEE Main 20245 questions in 5 shifts
- 6 Apr, Shift 1Q44Given below are two statements : Statement I : In an LCR series circuit, current is maximum at resonance. Statement II : Current in a…
Idea: Impedance at Resonance
EasyTwo statements - 6 Apr, Shift 2Q59For 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…
Idea: Resonant Frequency Calculation
EasyNumerical value - 8 Apr, Shift 1Q50A LCR circuit is at resonance for a capacitor C, inductance L and resistance R. Now the value of resistance is halved keeping all other…
Idea: Resistance Effect on Resonance Curve
EasySingle correct - 1 Feb, Shift 1Q43In series LCR circuit, the capacitance is changed from C to 4C. To keep the resonance frequency unchanged, the new inductance should be :
Idea: Resonant Frequency Calculation
EasySingle correct - 29 Jan, Shift 1Q43A capacitor of capacitance F is charged to a potential of 12 V and connected to a 6.4 mH inductor to produce oscillations. The…
Idea: LC Energy Oscillation at Resonance
Asked the year beforeEasySingle correct
JEE Main 20235 questions in 5 shifts
- 8 Apr, Shift 1Q57An oscillating LC circuit consists of a inductor and a capacitor. If the maximum charge to the…
Idea: LC Energy Oscillation at Resonance
Asked the year beforeEasyNumerical value - 8 Apr, Shift 2Q58A series combination of resistor of resistance 100 , inductor of inductance 1 H and capacitor of capacitance 6.25 F is…
Idea: Q-Factor Formula in L, C, R
New ideaEasyNumerical value - 10 Apr, Shift 1Q45Given below are two statements : Statement I : Maximum power is dissipated in a circuit containing an inductor, a capacitor and a resistor…
Idea: Power Factor at Resonance
Asked the year beforeEasyTwo statements - 11 Apr, Shift 1Q36As per the given graph, choose the correct representation for curve A and curve B. {Where = reactance of pure capacitive circuit…
Idea: Impedance vs Frequency Curve
New ideaEasyDiagram based · figure - 12 Apr, Shift 1Q35Given below are two statements: Statement I : When the frequency of an a.c source in a series LCR circuit increases, the current in the…
Idea: Power Factor at Resonance
Asked the year beforeEasyTwo statements
JEE Main 202213 questions in 12 shifts
- 25 Jul, Shift 1Q42To increase the resonant frequency in series LCR circuit,
Idea: Resonant Frequency Calculation
Asked the year beforeEasySingle correct - 25 Jul, Shift 2Q40When you walk through a metal detector carrying a metal object in your pocket, it raises an alarm. This phenomenon works on :
Idea: Resonance Condition
Asked the year beforeEasySingle correct - 26 Jul, Shift 1Q57The effective current I in the given circuit at very high frequencies will be __________ A.
Idea: High-Frequency Blocking in Series LCR
New ideaHardNumerical value · figure - 28 Jul, Shift 1Q54The frequencies at which the current amplitude in an LCR series circuit becomes times its maximum value, are 212 rad…
Idea: Half-Power Frequencies
New ideaMediumNumerical value - 29 Jul, Shift 2Q60A capacitor of capacitance 500 F is charged completely using a dc supply of 100 V. It is now connected to an inductor of inductance…
Idea: LC Energy Oscillation at Resonance
New ideaEasyNumerical value - 30 Jul, Shift 2Q23A sinusoidal voltage V(t) = 200 sin2000 t volt is applied to a series LCR circuit in which L = 10 mH, C = 25 µF and R =100 Ω. The…
Idea: Impedance at Resonance
Asked the year beforeEasyNumerical value - 25 Jun, Shift 2Q59In a series LCR circuit, the inductance, capacitance and resistance are = 100 mH, C= 100 µ and = respectively. They…
Idea: Impedance at Resonance
Asked the year beforeEasyNumerical value · figure - 26 Jun, Shift 1Q59A 110 V, 50 Hz, AC source is connected in the circuit (as shown in figure). The current through the resistance 55 , at resonance…
Idea: Parallel Resonance (Anti-resonance)
New ideaMediumNumerical value · figure - 28 Jun, Shift 1Q60A telegraph line of length 100 km has a capacity of 0.01 F/km and it carries an alternating current at 0.5 kilo cycle per second. If…
Idea: Resonant Frequency Calculation
Asked the year beforeEasyNumerical value - 29 Jun, Shift 1Q40For a series LCR circuit, I vs curve is shown : (a) To the left of , the circuit is mainly capacitive. (b) To the left…
Idea: Series LCR Capacitive Below Resonance
New ideaEasyOther · figure - 29 Jun, Shift 2Q60An inductor of 0.5 mH, a capacitor of 200 μF and a resistor of 2 Ω are connected in series with a 220 ac source. If the current is in…
Idea: Resonant Frequency Calculation
Asked the year beforeEasyNumerical value - 30 Jun, Shift 1Q46In series RLC resonator, if the self inductance and capacitance become double, the new resonant frequency () and new quality factor…
Idea: Q-Factor Formula in LCR
Asked the year beforeMediumSingle correct - 30 Jun, Shift 1Q57A series LCR circuit with R = and = is connected across a 220 V, 50 Hz…
Idea: Power Factor at Resonance
Asked the year beforeMediumNumerical value
JEE Main 202111 questions in 11 shifts
- 26 Aug, Shift 1Q10A series LCR circuit driven by 300 V at a frequency of 50 Hz contains a resistance R=3 k, an inductor of inductive reactance…
Idea: Resonance Condition
New ideaEasySingle correct - 31 Aug, Shift 1Q8In an ac circuit, an inductor, a capacitor and a resistor are connected in series with . Impedance of this circuit is :
Idea: Impedance at Resonance
New ideaEasySingle correct - 24 Feb, Shift 1Q26A resonance circuit having inductance and resistance H and 6.28 respectively oscillates at 10 MHz frequency. The…
Idea: Quality Factor Definition
New ideaEasyNumerical value - 24 Feb, Shift 2Q28A series LCR circuit is designed to resonate at an angular frequency . The circuit draws 16 W power from…
Idea: Power Factor at Resonance
New ideaEasyNumerical value - 25 Feb, Shift 1Q27A transmitting station releases waves of wavelength 960 m. A capacitor of F is used in the resonant circuit. The self…
Idea: Resonant Frequency Calculation
New ideaEasyNumerical value - 25 Feb, Shift 2Q12An LCR circuit contains resistance of and a supply of 220 V at 300 rad/s angular frequency. If only capacitance is removed…
Idea: Impedance at Resonance
New ideaMediumSingle correct - 26 Feb, Shift 1Q30In a series LCR resonant circuit, the quality factor is measured as 100. If the inductance is increased by two fold and resistance is…
Idea: Q-Factor Formula in LCR
New ideaEasyNumerical value - 26 Feb, Shift 2Q18Find the peak current and resonant frequency of the following circuit (as shown in figure).
Idea: Resonant Frequency Calculation
New ideaMediumDiagram based · figure - 22 Jul, Shift 2Q16Match List - I with List - II : List - I List - II (a) (i) Current is in phase with emf (b)…
Idea: Phase Angle Frequency Sweep
New ideaEasyMatch the list - 25 Jul, Shift 2Q25Two circuits are shown in the figure (a) & (b). At a frequency of __________ rad/s the average power dissipated in one cycle will be same…
Idea: Resonant Frequency Calculation
New ideaMediumNumerical value · figure - 18 Mar, Shift 1Q15In a series LCR resonance circuit, if we change the resistance only, from a lower to higher value :
Idea: Resistance Effect on Resonance Curve
New ideaMediumSingle correct
Questions from the official JEE Main Paper 1 shifts published by NTA (CBSE for 2017). Questions NTA dropped are left out. Topic and idea tags, counts and notes are Lumi’s.