JEE Main · Physics · Alternating Current
RMS and Peak Values: JEE Main previous year questions
14 questions in the 108 JEE Main shifts Lumi analysed, in 4 of 8 years. Pattern: Comes in cycles. 5 came in 2024–26. Here is how it is asked and which ideas come back.
- Questions
- 14
- in 14 of 108 shifts
- Years asked
- 4/8
- last asked 2025
- Weighted estimate
- 0.1
- model; history: 0.1 a shift on average, typically 0.0–0.2
Key findings
- 01
Asked in 4 of 8 years with analysed shifts and in 14 of 108 shifts: 14 questions, #164 of 196 topics. The years that asked it were 1.3 apart on average. Last asked in 2025.
- 02
64% of its questions since 2020 tested an idea no earlier year had asked; 2 repeated an idea from the year before.
- 03
The most repeated idea is Time from Peak to RMS, asked 3 times in 3 shifts (2021, 2022), most often as “time between peak and rms in ac”.
- 04
JEE Main has asked 8 of the 56 ideas in this topic; 46 have never been asked, directly or inside another question.
- 05
Mostly asked as single correct (79%); 21% need a numerical answer, 86% are easy and 0% hard.
- 06
The skill tested most is calculation (86%), then application (7%).
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: 5 in 24 shifts · 2022: 4 in 24 shifts · 2023: 0 in 12 shifts · 2024: 2 in 18 shifts · 2025: 3 in 8 shifts · 2026: 0 in 9 shifts.
- Up to 2023
- 0.1
- a shift, of 25
- Since 2024
- 0.2
- 0.1
- Usual gap
- 1.3 yrs
- between years asking it
- Shifts with it
- 14/108
- 13% of analysed shifts
How it is asked
Difficulty, format and skill
Across all 14 questions on RMS and Peak Values since 2017.
Difficulty
QUESTIONS- Easy12 · 86%
- Medium2 · 14%
- Hard0 · 0%
Format
SHARE- Single correct · 11 Q79%
- Numerical value · 3 Q21%
Skill tested
SHARE- Calculation · 12 Q86%
- Application · 1 Q7%
- Conceptual · 1 Q7%
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 8 of the 56 ideas in this topic. 46 have never been asked yet.
- Asked directly8 · 14%
- Touched inside another question2 · 4%
- Never asked46 · 82%
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.
- 24 Jun ’22 S1 · Q41A resistance of is connected to a source of alternating current rated 220 V, 50 Hz. Find the time taken by the current to…
easySingle correctAsked the year before
- 25 Jul ’21 S2 · Q15A 10 resistance is connected across 220 V - 50 Hz AC supply. The time taken by the current to change from its maximum value to…
easySingle correctNew idea
- 18 Mar ’21 S1 · Q6An AC source rated 220 V, 50 Hz is connected to a resistor. The time taken by the current to change from its maximum to the rms value is :
easySingle correctNew idea
- 24 Jun ’22 S1 · Q41
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
8 different ideas were tested; 5 came more than once.
time between peak and rms in ac
Single correct · 3 shiftsrms of current with dc offset
Numerical value · 2 shifts · 1 numericalrms of current with dc component
Numerical value · 2 shifts · 1 numericaltime between ac phase points
Single correct · 2 shiftsammeter reading in pure inductor circuit
Single correct · 2 shiftsaverage power in series lcr circuit
Numerical value · 1 shift · 1 numericalpeak value from rms and rating
Single correct · 1 shiftratio of heat in dc and ac
Single correct · 1 shift
| Idea | Years asked | Times | Shifts | Format | Numerical |
|---|---|---|---|---|---|
| Time from Peak to RMStime between peak and rms in ac | 3 | 3 | Single correctCalculation | – | |
| RMS of DC and AC Superpositionrms of current with dc offset | 2 | 2 | Numerical valueCalculation | 1 | |
| RMS Calculation via Integrationrms of current with dc component | 2 | 2 | Numerical valueApplication | 1 | |
| Time from Zero to Peaktime between ac phase points | 2 | 2 | Single correctCalculation | – | |
| AC Measuring Instrumentsammeter reading in pure inductor circuit | 2 | 2 | Single correctCalculation | – | |
| Power Calculation using RMSaverage power in series lcr circuit | 1 | 1 | Numerical valueCalculation | 1 | |
| Sinusoidal RMS-Peak Relationpeak value from rms and rating | 1 | 1 | Single correctCalculation | – | |
| Ratio of AC to DC Heat Dissipationratio of heat in dc and ac | 1 | 1 | Single correctCalculation | – |
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
RMS and Peak Values 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 20253 questions in 3 shifts
- 3 Apr, Shift 2Q37An 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 :
Idea: Sinusoidal RMS-Peak Relation
New ideaEasySingle correct - 7 Apr, Shift 1Q35An ac current is represented as Amp The r.m.s value of the current is
Idea: RMS of DC and AC Superposition
EasySingle correct - 7 Apr, Shift 2Q48An inductor of reactance , a capacitor of reactance , and a resistor of resistance are connected in…
Idea: Power Calculation using RMS
New ideaEasyNumerical value
JEE Main 20242 questions in 2 shifts
- 4 Apr, Shift 1Q58A alternating current at any instant is given by A. The rms value of the current is…
Idea: RMS Calculation via Integration
MediumNumerical value - 30 Jan, Shift 2Q43An alternating voltage volt is applied to a purely resistive load of . The time taken for the…
Idea: Time from Zero to Peak
MediumSingle correct
JEE Main 20224 questions in 4 shifts
- 27 Jul, Shift 1Q44A direct current of 4 A and an alternating current of peak value 4 A flow through resistance of 3 and 2 respectively.…
Idea: Ratio of AC to DC Heat Dissipation
New ideaEasySingle correct - 29 Jul, Shift 1Q43An alternating emf is applied to a circuit containing an inductance of H. If an a.c. ammeter…
Idea: AC Measuring Instruments
Asked the year beforeEasySingle correct - 24 Jun, Shift 1Q41A resistance of is connected to a source of alternating current rated 220 V, 50 Hz. Find the time taken by the current to…
Idea: Time from Peak to RMS
Asked the year beforeEasySingle correct - 27 Jun, Shift 1Q41The current flowing through an ac circuit is given by A How long will the current take to reach the peak value starting…
Idea: Time from Zero to Peak
New ideaEasySingle correct
JEE Main 20215 questions in 5 shifts
- 27 Aug, Shift 1Q28The alternating current is given by A The r.m.s. value…
Idea: RMS of DC and AC Superposition
New ideaEasyNumerical value - 26 Feb, Shift 1Q14An alternating current is given by the equation . The rms current will be :
Idea: RMS Calculation via Integration
New ideaEasySingle correct - 25 Jul, Shift 2Q15A 10 resistance is connected across 220 V - 50 Hz AC supply. The time taken by the current to change from its maximum value to…
Idea: Time from Peak to RMS
New ideaEasySingle correct - 17 Mar, Shift 1Q7An AC current is given by . A hot wire ammeter will give a reading :
Idea: AC Measuring Instruments
New ideaEasySingle correct - 18 Mar, Shift 1Q6An AC source rated 220 V, 50 Hz is connected to a resistor. The time taken by the current to change from its maximum to the rms value is :
Idea: Time from Peak to RMS
New ideaEasySingle 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.