JEE Main · Physics · Electrostatic Potential and Capacitance
Conductors in Fields: JEE Main previous year questions
13 questions in the 108 JEE Main shifts Lumi analysed, in 7 of 8 years. Pattern: Asked most years. 7 came in 2024–26. Here is how it is asked and which ideas come back.
- Questions
- 13
- in 12 of 108 shifts
- Years asked
- 7/8
- last asked 2026
- Weighted estimate
- 0.2
- model; history: 0.1 a shift on average, typically 0.0–0.2
Key findings
- 01
Asked in 7 of 8 years with analysed shifts and in 12 of 108 shifts: 13 questions, #165 of 196 topics.
- 02
77% of its questions since 2020 tested an idea no earlier year had asked; none repeated an idea from the year before.
- 03
The most repeated idea is Surface Charge Distribution, asked 2 times in 2 shifts (2022, 2026), most often as “assertion-reason on conductors in electrostatics”.
- 04
JEE Main has asked 10 of the 62 ideas in this topic; 50 have never been asked, directly or inside another question.
- 05
Mostly asked as single correct (62%); 8% need a numerical answer, 62% are easy and 0% hard.
- 06
The skill tested most is conceptual (46%), then application (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: 1 in 12 shifts · 2021: 1 in 24 shifts · 2022: 3 in 24 shifts · 2023: 1 in 12 shifts · 2024: 2 in 18 shifts · 2025: 3 in 8 shifts · 2026: 2 in 9 shifts.
- Up to 2023
- 0.1
- a shift, of 25
- Since 2024
- 0.2
- 0.2
- Usual gap
- 1.0 yrs
- between years asking it
- Shifts with it
- 12/108
- 11% of analysed shifts
How it is asked
Difficulty, format and skill
Across all 13 questions on Conductors in Fields since 2017.
Difficulty
QUESTIONS- Easy8 · 62%
- Medium5 · 38%
- Hard0 · 0%
Format
SHARE- Single correct · 8 Q62%
- Assertion–reason · 2 Q15%
- Other · 1 Q8%
- Numerical value · 1 Q8%
- Two statements · 1 Q8%
Skill tested
SHARE- Conceptual · 6 Q46%
- Application · 4 Q31%
- Calculation · 2 Q15%
- Multi-step · 1 Q8%
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 10 of the 62 ideas in this topic. 50 have never been asked yet.
- Asked directly10 · 16%
- Touched inside another question2 · 3%
- Never asked50 · 81%
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
Chapter, idea, question
Every idea JEE Main tested in this topic, with its eight years. Open one to read the questions.
8 ideas inside
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
10 different ideas were tested; 3 came more than once.
assertion-reason on conductors in electrostatics
Assertion–reason · 2 shiftscharge density ratio after contact
Single correct · 2 shiftscharge ratio of connected conducting spheres
Single correct · 2 shiftsfield ratio on connected spheres
Single correct · 1 shiftcompare surface charge density on irregular conductor
Other · 1 shiftassertion-reason on electrostatic shielding
Assertion–reason · 1 shiftapplication of grounding conductor
Single correct · 1 shiftradius of shell from equal potentials
Numerical value · 1 shift · 1 numericaltwo statements on conductor potential and surface field
Two statements · 1 shiftratio of surface fields of connected spheres
Single correct · 1 shift
| Idea | Years asked | Times | Shifts | Format | Numerical |
|---|---|---|---|---|---|
| Surface Charge Distributionassertion-reason on conductors in electrostatics | 2 | 2 | Assertion–reasonConceptual | – | |
| Surface Charge Density Ratio of Connected Spherescharge density ratio after contact | 2 | 2 | Single correctApplication | – | |
| Charge Ratio of Connected Distant Spherescharge ratio of connected conducting spheres | 2 | 2 | Single correctCalculation | – | |
| Surface Charge Density Ratio of Connected Spheresfield ratio on connected spheres | 1 | 1 | Single correctApplication | – | |
| Action of Points and Corona Dischargecompare surface charge density on irregular conductor | 1 | 1 | OtherConceptual | – | |
| Electrostatic Shieldingassertion-reason on electrostatic shielding | 1 | 1 | Assertion–reasonConceptual | – | |
| Earthing of Conductorsapplication of grounding conductor | 1 | 1 | Single correctConceptual | – | |
| Potential of Concentric Conducting Shellsradius of shell from equal potentials | 1 | 1 | Numerical valueCalculation | 1 | |
| Equipotential Nature of Conductorstwo statements on conductor potential and surface field | 1 | 1 | Two statementsConceptual | – | |
| Field at Conductor Surfaceratio of surface fields of connected spheres | 1 | 1 | Single correctApplication | – |
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
Conductors in Fields 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 20262 questions in 2 shifts
- 2 Apr, Shift 1Q34Two charged conducting spheres and of radii cm and cm are connected to each other by a wire. After equilibrium is…
Idea: Surface Charge Density Ratio of Connected Spheres
New ideaEasySingle correct - 4 Apr, Shift 2Q38Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A: In electrostatics, a…
Idea: Surface Charge Distribution
MediumAssertion–reason
JEE Main 20253 questions in 2 shifts
- 7 Apr, Shift 2Q38Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The outer body…
Idea: Electrostatic Shielding
New ideaEasyAssertion–reason - 8 Apr, Shift 2Q37Electric charge is transferred to an irregular metallic disk as shown in figure. If , , and are…
Idea: Action of Points and Corona Discharge
New ideaEasyOther · figure - 8 Apr, Shift 2Q38Two metal spheres of radius R and 3R have same surface charge density . If they are brought in contact and then separated, the…
Idea: Surface Charge Density Ratio of Connected Spheres
EasySingle correct
JEE Main 20242 questions in 2 shifts
- 5 Apr, Shift 2Q40The vehicles carrying inflammable fluids usually have metallic chains touching the ground :
Idea: Earthing of Conductors
New ideaEasySingle correct - 8 Apr, Shift 1Q45Two charged conducting spheres of radii and are connected to each other by a conducting wire. The ratio of charges of the two…
Idea: Charge Ratio of Connected Distant Spheres
EasySingle correct
JEE Main 20231 question in 1 shift
- 10 Apr, Shift 1Q55Three concentric spherical metallic shells , and of radius , and respectively have surface charge…
Idea: Potential of Concentric Conducting Shells
New ideaMediumNumerical value
JEE Main 20223 questions in 3 shifts
- 26 Jul, Shift 2Q35Two uniformly charged spherical conductors and of radii 5 mm and 10 mm are separated by a distance of 2 cm. If the spheres are…
Idea: Surface Charge Density Ratio of Connected Spheres
New ideaMediumSingle correct - 29 Jul, Shift 1Q41Given below are two statements. Statement I : Electric potential is constant within and at the surface of each conductor. Statement II :…
Idea: Equipotential Nature of Conductors
New ideaEasyTwo statements - 26 Jun, Shift 2Q40Sixty four conducting drops each of radius 0.02 m and each carrying a charge of 5 C are combined to form a bigger drop. The ratio of…
Idea: Surface Charge Distribution
New ideaMediumSingle correct
JEE Main 20211 question in 1 shift
- 3 Aug, Shift 1Q11Two conducting spheres of radii 15 and 12 are charged and joined by a wire. The ratio of electric fields on the surfaces of the…
Idea: Field at Conductor Surface
New ideaMediumSingle correct
JEE Main 20201 question in 1 shift
- 3 Sep, Shift 1Q10Two isolated conducting spheres S and S of radius R and R have 12 C and C charges,…
Idea: Charge Ratio of Connected Distant Spheres
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.