JEE Main · Physics · Electromagnetic Waves

X-Ray Production: JEE Main previous year questions

Name: X-Ray Production: JEE Main previous year questions
Creator: Lumi

4 questions in the 108 JEE Main shifts Lumi analysed, in 3 of 8 years. Pattern: Gone quiet. 0 came in 2024–26. Here is how it is asked and which ideas come back.

Questions: 4; in 3 of 108 shifts
Years asked: 3/8; last asked 2023
Since 2024: Quiet; 0 questions in 2024–26
Weighted estimate: –; history: 0.1 a shift on average, typically 0.0–0.1

Key findings

01
Asked in 3 of 8 years with analysed shifts and in 3 of 108 shifts: 4 questions, #195 of 196 topics. The years that asked it were 3.0 apart on average. Last asked in 2023.
02
100% of its questions since 2020 tested an idea no earlier year had asked; none repeated an idea from the year before.
03
No idea in this topic has been asked twice: every question tested something new.
04
JEE Main has asked 4 of the 58 ideas in this topic; 53 have never been asked, directly or inside another question.
05
Mostly asked as single correct (75%); 0% need a numerical answer, 75% are easy and 0% hard. It went down from 0.2 to 0.0 questions a shift since 2024.
06
The skill tested most is data or graph (50%), then recall (25%).

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: 1 in 1 shift · 2020: 0 in 12 shifts · 2021: 1 in 24 shifts · 2022: 0 in 24 shifts · 2023: 2 in 12 shifts · 2024: 0 in 18 shifts · 2025: 0 in 8 shifts · 2026: 0 in 9 shifts.

Up to 2023: 0.2; a shift, of 25
Since 2024: 0.0; -0.2
Usual gap: 3.0 yrs; between years asking it
Shifts with it: 3/108; 3% of analysed shifts

How it is asked

Difficulty, format and skill

Across all 4 questions on X-Ray Production since 2017.

Difficulty

QUESTIONS

Easy3 · 75%
Medium1 · 25%
Hard0 · 0%

Format

Single correct · 3 Q75%
Diagram based · 1 Q25%

Skill tested

Data or graph · 2 Q50%
Recall · 1 Q25%
Calculation · 1 Q25%

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 58 ideas in this topic. 53 have never been asked yet.

Asked directly4 · 7%
Touched inside another question1 · 2%
Never asked53 · 91%

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.

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

Open1 · 25%25%1/8
1 idea inside
- Open1 · 100%100%1/8
Open1 · 25%25%1/8
Open1 · 25%25%1/8
Open1 · 25%25%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; none came more than once.

Continuous Spectrum Origin1×
identify waves from electron bombardment
Single correct · 1 shift
Moseley's Law Graph Analysis1×
graph interpretation of moseley law
Diagram based · 1 shift
Cutoff Wavelength Calculation1×
shortest wavelength from tube voltage
Single correct · 1 shift
Cutoff Wavelength Shortcut Formula1×
graph of log cutoff wavelength vs log voltage
Single correct · 1 shift

Idea	Times	Shifts	Format	Numerical
Continuous Spectrum Originidentify waves from electron bombardment	1	1	Single correctRecall	–
Moseley's Law Graph Analysisgraph interpretation of moseley law	1	1	Diagram basedData or graph	–
Cutoff Wavelength Calculationshortest wavelength from tube voltage	1	1	Single correctCalculation	–
Cutoff Wavelength Shortcut Formulagraph of log cutoff wavelength vs log voltage	1	1	Single correctData or graph	–

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

X-Ray Production 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.