JEE Main · Physics · Current Electricity

Potentiometer: JEE Main previous year questions

Name: Potentiometer: JEE Main previous year questions
Creator: Lumi

13 questions in the 108 JEE Main shifts Lumi analysed, in 4 of 8 years. Pattern: Comes in cycles. 1 came in 2024–26. Here is how it is asked and which ideas come back.

Questions: 13; in 13 of 108 shifts
Years asked: 4/8; last asked 2024
Chance in a shift: 9%; calibrated model, how we compute it
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 13 of 108 shifts: 13 questions, #169 of 196 topics. The years that asked it were 1.3 apart on average. Last asked in 2024.
02
54% 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 Potential Gradient Calculation, asked 5 times in 5 shifts (2020, 2022), most often as “series resistance from null length”.
04
JEE Main has asked 4 of the 57 ideas in this topic; 48 have never been asked, directly or inside another question.
05
Mostly asked as numerical value (62%); 62% need a numerical answer, 31% are easy and 8% hard.
06
The skill tested most is calculation (54%), then multi-step (31%).

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: 2 in 12 shifts · 2021: 3 in 24 shifts · 2022: 7 in 24 shifts · 2023: 0 in 12 shifts · 2024: 1 in 18 shifts · 2025: 0 in 8 shifts · 2026: 0 in 9 shifts.

Up to 2023: 0.1; a shift, of 25
Since 2024: 0.0; -0.1
Usual gap: 1.3 yrs; between years asking it
Shifts with it: 13/108; 12% of analysed shifts

How it is asked

Difficulty, format and skill

Across all 13 questions on Potentiometer since 2017.

Difficulty

QUESTIONS

Easy4 · 31%
Medium8 · 62%
Hard1 · 8%

Format

Numerical value · 8 Q62%
Single correct · 3 Q23%
Diagram based · 2 Q15%

Skill tested

Calculation · 7 Q54%
Multi-step · 4 Q31%
Data or graph · 2 Q15%

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.

’17’20’21’22’23’24’25’26

Idea asked for the first time
Idea asked in an earlier year

Coverage of the topic

JEE Main has asked 4 of the 57 ideas in this topic. 48 have never been asked yet.

Asked directly4 · 7%
Touched inside another question5 · 9%
Never asked48 · 84%

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.

ideaAskedShareYears’17’20’21’22’23’24’25’26

OpenRepeated5 · 38%38%2/823
- 26 Jul ’22 S2 · Q59
  A potentiometer wire of length 300 cm is connected in series with a resistance 780 $\Omega$ and a standard cell of emf 4V. A constant…
  mediumNumerical value
- 28 Jul ’22 S1 · Q55
  As shown in the figure, a potentiometer wire of resistance 20 $\Omega$ and length 300 cm is connected with resistance box (R.B.) and a…
  hardNumerical value
- 24 Jun ’22 S2 · Q53
  A potentiometer wire of length 10 m and resistance 20 $\Omega$ is connected in series with a 25 V battery and an external resistance 30…
  mediumNumerical value
- 8 Jan ’20 S1 · Q20
  The length of a potentiometer wire is 1200 cm and it carries a current of 60 mA. For a cell of emf 5 V and internal resistance of 20…
  mediumSingle correctNew idea
- 2 Sep ’20 S2 · Q20
  A potentiometer wire PQ of 1 m length is connected to a standard cell E $_1$ . Another cell E $_2$ of emf 1.02 V is connected with a…
  easyDiagram basedNew idea
OpenRepeated4 · 31%31%2/822
OpenRepeated3 · 23%23%2/82
Open1 · 8%8%1/8

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

4 different ideas were tested; 3 came more than once.

Potential Gradient Calculation5×
series resistance from null length
Numerical value · 5 shifts · 3 numerical
Comparing EMF of Two Cells4×
balancing length from emf ratio
Numerical value · 4 shifts · 3 numerical
Internal Resistance Measurement3×
internal resistance by potentiometer
Numerical value · 3 shifts · 2 numerical
Maximum Measurable Voltage Limit1×
maximum measurable emf of potentiometer
Single correct · 1 shift

Idea	Times	Shifts	Format	Numerical
Potential Gradient Calculationseries resistance from null length	5	5	Numerical valueMulti-step	3
Comparing EMF of Two Cellsbalancing length from emf ratio	4	4	Numerical valueCalculation	3
Internal Resistance Measurementinternal resistance by potentiometer	3	3	Numerical valueCalculation	2
Maximum Measurable Voltage Limitmaximum measurable emf of potentiometer	1	1	Single correctMulti-step	–

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

Potentiometer 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.

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.

Key findings

Questions a shift, year by year

Difficulty, format and skill

Difficulty

Format

Skill tested

New idea, or one asked before?

Coverage of the topic

Idea, year, question

Every idea inside this topic

Potentiometer questions, year by year

JEE Main 20241 question in 1 shift

JEE Main 20227 questions in 7 shifts

JEE Main 20213 questions in 3 shifts

JEE Main 20202 questions in 2 shifts

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