JEE Main · Physics · Semiconductor Electronics: Materials, Devices and Simple Circuits

Logic Gates: JEE Main previous year questions

Name: Logic Gates: JEE Main previous year questions
Creator: Lumi

47 questions in the 108 JEE Main shifts Lumi analysed, in 7 of 8 years. Pattern: Asked most years. 17 came in 2024–26. Here is how it is asked and which ideas come back.

Questions: 47; in 46 of 108 shifts
Years asked: 7/8; last asked 2026
Chance in a shift: 47%; calibrated model, how we compute it
Weighted estimate: 0.4; model; history: 0.4 a shift on average, typically 0.2–0.5

Key findings

01
Asked in 7 of 8 years with analysed shifts and in 46 of 108 shifts: 47 questions, #64 of 196 topics.
02
23% of its questions since 2020 tested an idea no earlier year had asked; 34 repeated an idea from the year before.
03
The most repeated idea is Combinational Logic Circuits, asked 31 times in 31 shifts (2020, 2021, 2022, 2023, 2024, 2025, 2026), most often as “identify output of combinational logic circuit”.
04
JEE Main has asked 9 of the 55 ideas in this topic; 41 have never been asked, directly or inside another question.
05
Mostly asked as diagram based (87%); 0% need a numerical answer, 38% are easy and 2% hard.
06
The skill tested most is diagram reading (62%), then application (19%).

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: 4 in 12 shifts · 2021: 15 in 24 shifts · 2022: 5 in 24 shifts · 2023: 6 in 12 shifts · 2024: 8 in 18 shifts · 2025: 4 in 8 shifts · 2026: 5 in 9 shifts.

Up to 2023: 0.3; a shift, of 25
Since 2024: 0.5; 0.2
Usual gap: 1.0 yrs; between years asking it
Shifts with it: 46/108; 43% of analysed shifts

Recent framings

output waveform of combinational circuit
identify output of combinational logic circuit
identify input combination from logic circuit

Revise first

Combinational Logic Circuits · asked 2020, 2021, 2022, 2023, 2024, 2025, 2026
Timing Diagrams and Waveform Analysis · asked 2021, 2022, 2023, 2026
Gate Realization using Universal · asked 2020, 2023

How it is asked

Difficulty, format and skill

Across all 47 questions on Logic Gates since 2017.

Difficulty

QUESTIONS

1828

Easy18 · 38%
Medium28 · 60%
Hard1 · 2%

Format

Diagram based · 41 Q87%
Single correct · 5 Q11%
Two statements · 1 Q2%

Skill tested

Diagram reading · 29 Q62%
Application · 9 Q19%
Data or graph · 7 Q15%
Multi-step · 1 Q2%
Conceptual · 1 Q2%

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 9 of the 55 ideas in this topic. 41 have never been asked yet.

9541

Asked directly9 · 16%
Touched inside another question5 · 9%
Never asked41 · 75%

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

OpenRepeated31 · 66%66%7/82102844
- 2 Apr ’26 S2 · Q30
  If X and Y are the inputs, the given circuit works as
  mediumDiagram basedAsked the year before
- 4 Apr ’26 S1 · Q38
  Two $4$ bits binary numbers, $A=1101$ and $B=1010$ are given in the inputs of a logic circuit shown in figure below. The output ( $Y$ ) will…
  easyDiagram basedAsked the year before
- 5 Apr ’26 S1 · Q45
  For the given logic circuit, which of the following inputs combination will make both LED-1 and LED-2 to glow?
  easyDiagram basedAsked the year before
- 6 Apr ’26 S2 · Q43
  Refer to the logic circuit given below. For two inputs ( $A=1$ , $B=1$ ) and ( $A=0$ , $B=1$ ), output ( $Y$ ) will be __________.
  easyDiagram basedAsked the year before
- 2 Apr ’25 S2 · Q39
  In the digital circuit shown in the figure, for the given inputs the P and Q values are :
  mediumDiagram basedAsked the year before
- 3 Apr ’25 S1 · Q45
  Choose the correct logic circuit for the given truth table having inputs A and B. Inputs A, B / Output Y: A=0,B=0: Y=0 A=0,B=1: Y=0…
  mediumDiagram basedAsked the year before
- 3 Apr ’25 S2 · Q45
  The truth table corresponding to the circuit given below is :
  easyDiagram basedAsked the year before
- 7 Apr ’25 S2 · Q45
  Consider the following logic circuit. The output is $Y=0$ when :
  easyDiagram basedAsked the year before
- 4 Apr ’24 S2 · Q49
  Identify the logic gate given in the circuit:
  easyDiagram basedAsked the year before
- 5 Apr ’24 S1 · Q49
  Following gates section is connected in a complete suitable circuit. For which of the following combination, bulb will glow (ON) :
  mediumDiagram basedAsked the year before
- 5 Apr ’24 S2 · Q50
  The output (Y) of logic circuit given below is 0 only when :
  easySingle correctAsked the year before
- 6 Apr ’24 S1 · Q49
  The correct truth table for the following logic circuit is :
  easyDiagram basedAsked the year before
- 8 Apr ’24 S1 · Q47
  The output Y of following circuit for given inputs is :
  mediumDiagram basedAsked the year before
- 9 Apr ’24 S2 · Q48
  In the truth table of the above circuit the value of X and Y are :
  mediumSingle correctAsked the year before
- 31 Jan ’24 S1 · Q48
  Identify the logic operation performed by the given circuit.
  easySingle correctAsked the year before
- 31 Jan ’24 S2 · Q48
  The output of the given circuit diagram is -
  mediumDiagram basedAsked the year before
- 11 Apr ’23 S2 · Q42
  The logic operations performed by the given digital circuit is equivalent to:
  mediumDiagram basedAsked the year before
- 25 Jun ’22 S2 · Q48
  Identify the logic operation performed by the given circuit :
  mediumDiagram basedAsked the year before
- 28 Jun ’22 S1 · Q46
  In the following circuit, the correct relation between output (Y) and inputs A and B will be :
  mediumDiagram basedAsked the year before
- 3 Aug ’21 S2 · Q17
  Read the question
  mediumSingle correctAsked the year before
- 26 Aug ’21 S1 · Q3
  Read the question
  easyDiagram basedAsked the year before
- 26 Aug ’21 S2 · Q4
  Read the question
  mediumDiagram basedAsked the year before
- 31 Aug ’21 S1 · Q2
  Read the question
  easyDiagram basedAsked the year before
- 24 Feb ’21 S2 · Q20
  Read the question
  mediumDiagram basedAsked the year before
- 25 Feb ’21 S2 · Q20
  Read the question
  mediumDiagram basedAsked the year before
- 25 Jul ’21 S1 · Q12
  Read the question
  easyDiagram basedAsked the year before
- 16 Mar ’21 S2 · Q20
  Read the question
  mediumDiagram basedAsked the year before
- 17 Mar ’21 S1 · Q17
  Read the question
  mediumDiagram basedAsked the year before
- 17 Mar ’21 S2 · Q15
  Read the question
  mediumDiagram basedAsked the year before
- 8 Jan ’20 S1 · Q19
  Read the question
  mediumSingle correctNew idea
- 2 Sep ’20 S2 · Q19
  Read the question
  mediumDiagram basedNew idea
OpenRepeated7 · 15%15%4/8222
OpenRepeated2 · 4%4%2/8
OpenRepeated2 · 4%4%2/8
Open1 · 2%2%1/8
Open1 · 2%2%1/8
Open1 · 2%2%1/8
Open1 · 2%2%1/8
Open1 · 2%2%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

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

Combinational Logic Circuits31×
identify output of combinational logic circuit
Diagram based · 31 shifts
Timing Diagrams and Waveform Analysis7×
output waveform of combinational circuit
Diagram based · 7 shifts
Gate Realization using Universal2×
identify gate from combinational circuit
Diagram based · 2 shifts
Diode Realization of OR and AND Gates2×
identify output of combinational logic circuit
Diagram based · 2 shifts
Electrical Switch Analogies for Logic Gates1×
identify gate from combinational circuit
Diagram based · 1 shift
Universal Gates NAND and NOR1×
identify output of logic gate from timing diagram
Diagram based · 1 shift
Basic Gates Truth Tables1×
statement i/ii on logic gates
Two statements · 1 shift
Transistor Realization of NAND Gate1×
identify gate from transistor circuit
Diagram based · 1 shift
SR Latch using NAND Gates1×
output of nand-based logic circuit with feedback
Diagram based · 1 shift

Idea	Times	Shifts	Format	Numerical
Combinational Logic Circuitsidentify output of combinational logic circuit	31	31	Diagram basedDiagram reading	–
Timing Diagrams and Waveform Analysisoutput waveform of combinational circuit	7	7	Diagram basedData or graph	–
Gate Realization using Universalidentify gate from combinational circuit	2	2	Diagram basedDiagram reading	–
Diode Realization of OR and AND Gatesidentify output of combinational logic circuit	2	2	Diagram basedDiagram reading	–
Electrical Switch Analogies for Logic Gatesidentify gate from combinational circuit	1	1	Diagram basedDiagram reading	–
Universal Gates NAND and NORidentify output of logic gate from timing diagram	1	1	Diagram basedData or graph	–
Basic Gates Truth Tablesstatement i/ii on logic gates	1	1	Two statementsConceptual	–
Transistor Realization of NAND Gateidentify gate from transistor circuit	1	1	Diagram basedDiagram reading	–
SR Latch using NAND Gatesoutput of nand-based logic circuit with feedback	1	1	Diagram basedDiagram reading	–

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

Logic Gates questions, year by year

The newest 40 show their opening words as they appeared in the official paper; older ones name the idea they tested. Open one for its options and the official answer.

JEE Main 20265 questions in 5 shifts

2 Apr, Shift 2Q30
If X and Y are the inputs, the given circuit works as
Idea: Combinational Logic Circuits
Asked the year beforeMediumDiagram based · figure
4 Apr, Shift 1Q38
Two $4$ bits binary numbers, $A=1101$ and $B=1010$ are given in the inputs of a logic circuit shown in figure below. The output ( $Y$ ) will…
Idea: Combinational Logic Circuits
Asked the year beforeEasyDiagram based · figure
5 Apr, Shift 1Q45
For the given logic circuit, which of the following inputs combination will make both LED-1 and LED-2 to glow?
Idea: Combinational Logic Circuits
Asked the year beforeEasyDiagram based · figure
6 Apr, Shift 2Q43
Refer to the logic circuit given below. For two inputs ( $A=1$ , $B=1$ ) and ( $A=0$ , $B=1$ ), output ( $Y$ ) will be __________.
Idea: Combinational Logic Circuits
Asked the year beforeEasyDiagram based · figure
8 Apr, Shift 2Q45
The output $Y$ for the given inputs $A$ and $B$ to the circuit is :
Idea: Timing Diagrams and Waveform Analysis
MediumDiagram based · figure

JEE Main 20254 questions in 4 shifts

2 Apr, Shift 2Q39
In the digital circuit shown in the figure, for the given inputs the P and Q values are :
Idea: Combinational Logic Circuits
Asked the year beforeMediumDiagram based · figure
3 Apr, Shift 1Q45
Choose the correct logic circuit for the given truth table having inputs A and B. Inputs A, B / Output Y: A=0,B=0: Y=0 A=0,B=1: Y=0…
Idea: Combinational Logic Circuits
Asked the year beforeMediumDiagram based · figure
3 Apr, Shift 2Q45
The truth table corresponding to the circuit given below is :
Idea: Combinational Logic Circuits
Asked the year beforeEasyDiagram based · figure
7 Apr, Shift 2Q45
Consider the following logic circuit. The output is $Y=0$ when :
Idea: Combinational Logic Circuits
Asked the year beforeEasyDiagram based · figure

JEE Main 20248 questions in 8 shifts

4 Apr, Shift 2Q49
Identify the logic gate given in the circuit:
Idea: Combinational Logic Circuits
Asked the year beforeEasyDiagram based · figure
5 Apr, Shift 1Q49
Following gates section is connected in a complete suitable circuit. For which of the following combination, bulb will glow (ON) :
Idea: Combinational Logic Circuits
Asked the year beforeMediumDiagram based · figure
5 Apr, Shift 2Q50
The output (Y) of logic circuit given below is 0 only when :
Idea: Combinational Logic Circuits
Asked the year beforeEasySingle correct · figure
6 Apr, Shift 1Q49
The correct truth table for the following logic circuit is :
Idea: Combinational Logic Circuits
Asked the year beforeEasyDiagram based · figure
8 Apr, Shift 1Q47
The output Y of following circuit for given inputs is :
Idea: Combinational Logic Circuits
Asked the year beforeMediumDiagram based · figure
9 Apr, Shift 2Q48
In the truth table of the above circuit the value of X and Y are :
Idea: Combinational Logic Circuits
Asked the year beforeMediumSingle correct · figure
31 Jan, Shift 1Q48
Identify the logic operation performed by the given circuit.
Idea: Combinational Logic Circuits
Asked the year beforeEasySingle correct · figure
31 Jan, Shift 2Q48
The output of the given circuit diagram is -
Idea: Combinational Logic Circuits
Asked the year beforeMediumDiagram based · figure

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.