The truth table for the following logic circuit is:
1
A
2
B
3
C
4
D
Official Solution
Correct Option: (1)
Let's analyze the logic circuit step-by-step. The circuit has two inputs, A and B. There are two NOT gates, two AND gates, and one OR gate. The input to the top AND gate are A and the output of the NOT gate connected to B. So, the inputs are A and . The output of this AND gate is . The input to the bottom AND gate are B and the output of the NOT gate connected to A. So, the inputs are B and . The output of this AND gate is . The outputs of the two AND gates, and , are the inputs to the final OR gate. The final output is . This is the Boolean expression for the Exclusive OR (XOR) gate. Let's construct the truth table for this expression: Case 1: A=0, B=0. . Case 2: A=0, B=1. . Case 3: A=1, B=0. . Case 4: A=1, B=1. . The final truth table is: A | B | Y
--|---|--
0 | 0 | 0
0 | 1 | 1
1 | 0 | 1
1 | 1 | 0 This matches the truth table given in option (A).
03
PYQ 2021
medium
physicsID: jee-main
Find the truth table for the function Y of A and B represented in the following figure.
1
A
2
B
3
C
4
D
Official Solution
Correct Option: (3)
From the given logic circuit: The upper gate is an AND gate with inputs and . The lower branch takes input through a NOT gate. These two outputs are connected to an OR gate. Hence the output function is: Now simplify using Boolean algebra: Since: Truth Table for
04
PYQ 2022
medium
physicsID: jee-main
A logic gate circuit has two inputs A and B and output Y. The voltage waveforms of A, B and Y are shown below.
Fig. Logic gate circuit
The logic gate circuit is :
1
AND gate
2
OR gate
3
NOR gate
4
NAND gate
Official Solution
Correct Option: (1)
To determine the logic gate circuit, we need to analyze the given voltage waveforms for inputs A, B, and output Y:
Fig. Logic gate circuit
From the waveform:
Observe when both inputs A and B are high (1), the output Y is also high (1).
When either A or B is low (0), the output Y is low (0).
This behavior is consistent with an AND gate, which outputs high only when all its inputs are high.
Verification Against Options:
AND gate: Matches the observed behavior (correct).
OR gate: Would output high if any input is high (does not match).
NOR gate: Inverse of OR gate, would output low if any input is high (does not match).
NAND gate: Inverse of AND gate, would output low only if all inputs are high (does not match).
Therefore, the logic gate circuit is indeed an AND gate.
05
PYQ 2022
medium
physicsID: jee-main
Identify the correct Logic Gate for the following output (Y) of two inputs A and B.
1
2
3
4
Official Solution
Correct Option: (2)
A
B
Y
0
0
1
0
1
1
1
0
1
1
1
0
Hence, the correct option is (B):
06
PYQ 2023
easy
physicsID: jee-main
For the logic circuit shown, the output waveform at Y is:
Official Solution
Correct Option: (1)
07
PYQ 2023
medium
physicsID: jee-main
The output waveform of the given logical circuit for the following inputs and as shown below, is :
1
2
3
4
Official Solution
Correct Option: (3)
(A⋅A)=A B⋅B=B (A⋅B)=A+B
OR Gate
08
PYQ 2023
medium
physicsID: jee-main
The logic operations performed by the given digital circuit is equivalent to:
1
NAND
2
NOR
3
OR
4
AND
Official Solution
Correct Option: (4)
Step 1: Analyze the First NAND Gate
The output of the first (topmost) NAND gate is:
This output is also connected as an input to the second NAND gate (middle). Let this output be :
Step 2: Analyze the Second NAND Gate
The second NAND gate takes and the output of the third NAND gate ( ) as inputs. The output of the second NAND gate is:
From the first NAND gate, , and from the third NAND gate, . Substituting these values:
Using the property of NAND gates:
Step 3: Analyze the NOT Gate
The NOT gate inverts the output of the second NAND gate. Let be the output of the NOT gate. Then:
Substituting :
Step 4: Simplify the Expression
Using Boolean algebra, the final output simplifies to:
This represents the logic for an AND gate.
Final Answer:
The given digital circuit is equivalent to an AND gate.
09
PYQ 2023
medium
physicsID: jee-main
Which logic gate is specified by given circuit
1
AND
2
OR
3
NAND
4
NOR
Official Solution
Correct Option: (4)
The correct answer is (D): NOR.
A
B
0
0
1
1
0
0
0
1
0
1
1
0
10
PYQ 2023
medium
physicsID: jee-main
The logic gate equivalent to the given circuit diagram is :
1
OR
2
NAND
3
NOR
4
AND
Official Solution
Correct Option: (2)
The circuit diagram represents a NAND gate. Let’s analyze the behavior of the circuit:
When both switches and are closed (ON state), the output is 0 (the bulb does not glow) because the current flows directly to the ground.
In all other cases, the bulb glows, corresponding to an output of 1.
This behavior matches the truth table of a NAND gate:
Thus, the circuit corresponds to the logic of a NAND gate, with the output given by:
11
PYQ 2023
medium
physicsID: jee-main
The output from a NAND gate having inputs A and B given below will be.
1
2
3
4
Official Solution
Correct Option: (2)
A NAND gate produces an output that is the negation of the AND gate output. The output ( ) is given by: where and are the inputs to the NAND gate. The truth table for a NAND gate is as follows:
Step-by-Step Analysis of the Inputs and Outputs: - When both and , the output . - When and , the output . - When and , the output . - When both and , the output . Now analyze the given input waveforms for and : 1. For each interval where and are given, calculate . 2. Take the negation ( ) to find the output . From the given inputs and truth table, the output waveform matches Option (2).
12
PYQ 2023
medium
physicsID: jee-main
Consider a combination of gates as shown:
1
2
3
4
Official Solution
Correct Option: (1)
Given Expression:
In this expression, we have two components: A and B. The symbol ' represents the NOT operation, which inverts the value of the variable.
We begin by interpreting the term A'B' as the AND operation between the negation (NOT) of A and B. In Boolean algebra, the product (AND operation) of A' and B' can be represented as:
Now, according to the given equation, the result y is also equal to the sum (OR operation) of A and B. The OR operation between A and B is written as:
Therefore, we conclude that the expression represents the behavior of an OR gate in digital logic. The OR gate will output 1 (True) if either of the inputs A or B is 1, and it will output 0 (False) only when both inputs are 0.
Conclusion: The given equation represents the logic of an OR gate. Hence, the correct option is (A) OR gate.
13
PYQ 2023
medium
physicsID: jee-main
Name the logic gate equivalent to the diagram attached
1
NOR
2
OR
3
NAND
4
AND
Official Solution
Correct Option: (1)
Circuit is closed when neither A nor B is closed ⇒ current flows for A = 0 B = 0 when either or both of A & B is closed we get current bypass from switch. Hence it is “NOR” gate.
14
PYQ 2023
medium
physicsID: jee-main
At any instant the velocity of a particle of mass 500 g is . If the force acting on the particle at t=1s is . Then the value of x will be:
1
6
2
4
3
3
4
2
Official Solution
Correct Option: (3)
Step 1: Calculate acceleration.
At t = 1s:
Step 2: Calculate force.- Given mass m = 500g = 0.5kg:
Final Answer: The value of x is 3
15
PYQ 2023
hard
physicsID: jee-main
For the given logic gates combination, the correct truth table will be
1
A
B
X
0
0
1
1
0
1
0
1
1
0
0
0
2
A
B
X
0
0
1
1
0
1
0
1
0
1
1
1
3
A
B
X
0
0
1
1
0
1
0
1
0
1
1
0
4
A
B
X
0
0
1
1
0
1
0
1
1
0
1
0
Official Solution
Correct Option: (3)
The given circuit consists of a combination of NOT, AND, and OR gates. The truth table is derived as follows: 1. The NOT gates invert the inputs and . 2. These inverted values are then input into the AND gates, and the output of each AND gate is determined. 3. Finally, the outputs of the AND gates are fed into the OR gate to produce the final output . Truth Table Analysis: (A) When and , the output .
(B) When and , the output .
(C) When and , the output .
(D) When and , the output .
Hence, the correct truth table corresponds to Table 3.
16
PYQ 2024
easy
physicsID: jee-main
In the truth table of the above circuit the value of X and Y are
1
1,1
2
1,0
3
0,1
4
0,0
Official Solution
Correct Option: (1)
To solve the given problem, we need to analyze the logic circuit and determine the output for the inputs and , which correspond to finding and in the truth table. Let's break it down step-by-step:
1. Analyzing the Circuit:
The circuit consists of an AND gate, a NAND gate, and a NOR gate.
Variables and are listed in the truth table for different input values of and .
2. Calculating the Output:
Case 1: (Find )
AND Gate: The input is . Output of AND gate is .
NAND Gate: Inputs are and inverted output of AND gate (since NOR gate is connected here), which is 1. Output is: .
NOR Gate Output : Inputs are . Output is .
Thus, for , the output .
Case 2: (Find )
AND Gate: The input is . Output of AND gate is .
NAND Gate: Inputs are and inverted output of AND gate, which is 1. Output is: .
NOR Gate Output : Inputs are . Output is .
Thus, for , the output .
Conclusion:
From the analysis, both and are 1 for the respective inputs and configurations. Therefore, the correct answer is 1,1.
17
PYQ 2024
easy
physicsID: jee-main
Following gates section is connected in a complete suitable circuit. For which of the following combination, bulb will glow (ON):
1
A = 0, B = 1, C = 1, D = 1
2
A = 1, B = 0, C = 0, D = 0
3
A = 0, B = 0, C = 0, D = 1
4
A = 1, B = 1, C = 1, D = 0
Official Solution
Correct Option: (2)
The bulb will glow if it experiences a potential drop across it. This requires one end of the bulb to be at a high state (1) and the other end to be at a low state (0).
In Option (2), setting satisfies this condition, as it results in the output of the OR gate being high, creating the required potential drop across the bulb.
18
PYQ 2024
medium
physicsID: jee-main
The output of the given circuit diagram is
1
2
3
4
Official Solution
Correct Option: (3)
The circuit diagram provided is a logic gate combination circuit. Let's analyze the circuit step-by-step to determine the output for different input combinations of and .
The circuit contains:
An NOT gate inverts the input .
Two AND gates and one OR gate are used to process the signals.
We will calculate the output for each input combination in the truth table:
Inputs: ,
The NOT gate inverts (0 becomes 1).
The first AND gate has inputs and NOT , so its output is .
The second AND gate has inputs (inverted becomes 1) and , so its output is .
The OR gate processes the outputs and , resulting in .
Inputs: ,
The NOT gate inverts (0 becomes 1).
The first AND gate has inputs and NOT , so its output is .
The second AND gate has inputs (inverted becomes 1) and , so its output is .
The OR gate processes the outputs and , resulting in .
Inputs: ,
The NOT gate inverts (1 becomes 0).
The first AND gate has inputs and NOT , so its output is .
The second AND gate has inputs (inverted becomes 0) and , so its output is .
The OR gate processes the outputs and , resulting in .
Inputs: ,
The NOT gate inverts (1 becomes 0).
The first AND gate has inputs and NOT , so its output is .
The second AND gate has inputs (inverted becomes 0) and , so its output is .
The OR gate processes the outputs and , resulting in .
Based on the above analysis, the correct truth table is:
A
B
Y
0
0
0
1
0
1
0
1
0
1
1
0
Hence, the correct answer is:
19
PYQ 2024
medium
physicsID: jee-main
The output Y of following circuit for given inputs is :
1
2
3
0
4
Official Solution
Correct Option: (3)
To solve this problem, we need to analyze the logic circuit depicted in the given image. The circuit consists of AND, OR, and NOT gates.
Let's break down the circuit step-by-step:
The input A is connected to both an OR gate and an AND gate.
The input B is connected to a NOT gate. Thus, it outputs .
The OR gate takes inputs A and B, resulting in the output .
The AND gate combines input A and NOT B, giving the output .
Finally, these two outputs from the OR and the AND gates are inputs to another AND gate, thus:
The final output Y from the AND gate is:
We analyze this expression:
The term means A is true and B is false.
The expression evaluates to true if either A or B is true.
Combining with in an AND operation results in:
If A is true and B is false, is true, but for the AND operation with to hold, B must be false.
If B is true, becomes false, leading the overall expression to false.
Therefore, the output Y will always be zero because the condition for it to be true is not exclusively satisfied.
Conclusion: The correct answer is .
20
PYQ 2024
easy
physicsID: jee-main
The correct truth table for the following logic circuit is :
1
2
3
4
Official Solution
Correct Option: (2)
The circuit consists of an AND gate, a NOT gate, and an OR gate. The output is determined as follows:
The output of the AND gate is .
The output of the NOT gate is .
The output is the OR of and :
Step-by-Step Evaluation of Truth Table:
A
B
A · B
A · B
Y = A · B + B
0
0
0
1
1
0
1
0
1
1
1
0
0
1
1
1
1
1
0
1
Thus, the correct truth table is represented in Option (2).
21
PYQ 2024
hard
physicsID: jee-main
Draw truth table of given gate circuit.
1
2
3
4
Official Solution
Correct Option: (1)
The Correct Option is (B) :
22
PYQ 2024
medium
physicsID: jee-main
Identify the logic gate given in the circuit :
1
NAND - gate
2
OR - gate
3
AND gate
4
NOR gate
Official Solution
Correct Option: (2)
To identify the logic gate in the given circuit, let's analyze the image provided.
The circuit consists of two inputs, A and B, connected to an OR gate. The behavior of an OR gate is as follows:
If either input A or B is high (1), or both are high, the output Y is high (1).
If both inputs A and B are low (0), the output Y is low (0).
The logical operation performed by an OR gate can be described by the expression:
Y = A + B
Where '+' denotes the logical OR operation.
Now let's examine each option:
NAND gate: Outputs low only if both inputs are high. This does not match the circuit's behavior.
OR gate: Outputs high if at least one input is high, which matches the circuit's behavior.
AND gate: Outputs high only if both inputs are high. This does not match the circuit's behavior.
NOR gate: Outputs high only if both inputs are low. This does not match the circuit's behavior.
Considering the explanation above, the correct answer is indeed the OR gate.
23
PYQ 2024
medium
physicsID: jee-main
The truth table for this given circuit is :The truth table for this given circuit is :
1
A
B
Y
0
0
1
0
1
1
1
0
1
1
1
0
2
A
B
Y
0
0
0
0
1
1
1
0
0
1
1
1
3
A
B
Y
0
0
0
0
1
0
1
0
0
1
1
1
4
A
B
Y
0
0
1
0
1
0
1
0
1
1
1
0
Official Solution
Correct Option: (2)
To determine the truth table for the given circuit, we need to analyze the logic gates involved and the connections between the inputs and outputs.
Here's how the circuit works:
The circuit includes an OR gate and a NOT gate at the input A, as well as an AND gate.
The input A is connected to a NOT gate, meaning the output of the NOT gate is .
This is then fed into an OR gate along with input B.
The output of the OR gate is .
Finally, this result is fed into an AND gate along with input B to produce the output .
Now, let’s evaluate the output Y for each combination of A and B:
A
B
Y
0
0
0
0
1
1
1
0
0
1
1
1
The correct truth table for the given circuit is the one matching these outputs, which corresponds to:
A
B
Y
0
0
0
0
1
1
1
0
0
1
1
1
24
PYQ 2024
medium
physicsID: jee-main
The output (Y) of logic circuit given below is 0 only when :
1
A = 1, B = 0
2
A = 0, B = 0
3
A = 1, B = 1
4
A = 0, B = 1
Official Solution
Correct Option: (2)
To determine when the output of the given logic circuit is 0, we analyze the circuit’s components and their behavior with inputs and .
Step 1: Identifying Logic Gates From the circuit: - There is an OR gate taking inputs and . - Another OR gate takes input from the output of the first OR gate and a constant input 1. - There is an AND gate with inputs and , whose output feeds into the final OR gate.
Step 2: Analyzing the Behavior of the Circuit 1. The first OR gate outputs 1 if either or . The output of this OR gate is 0 only if both and . 2. The second OR gate has one input fixed as 1. Since an OR gate outputs 1 if any input is 1, this gate will always output 1 regardless of the input from the first OR gate. 3. The AND gate outputs 1 only if both and . In all other cases, it outputs 0. 4. The output is determined by the final OR gate, which takes inputs from the AND gate and the second OR gate. Since the second OR gate always outputs 1, the only way for to be 0 is for all other inputs (AND gate output) to be 0.
Step 3: Condition for For the output to be 0, the input conditions must be such that the output from the AND gate is 0 (which happens when and ).
Therefore, the correct condition is:
Hence, the correct option is (2).
25
PYQ 2024
medium
physicsID: jee-main
The truth table for the combination of logical gates
1
2
3
4
Official Solution
Correct Option: (3)
The correct option is (C):
26
PYQ 2025
medium
physicsID: jee-main
A particle oscillates along the -axis according to the law, , where and is the time period of oscillation. The kinetic energy ( ) of the particle as a function of is correctly represented by the graph:
1
2
3
4
Official Solution
Correct Option: (1)
The kinetic energy of a particle is given by: where is the velocity of the particle. The velocity is the derivative of the displacement with respect to time: Thus, the velocity is proportional to , and the kinetic energy is proportional to the square of the velocity, which results in a graph where the kinetic energy increases as the particle moves from the origin to its maximum displacement and decreases symmetrically thereafter. Final Answer: Graph 1.
27
PYQ 2025
medium
physicsID: jee-main
At the interface between two materials having refractive indices and , the critical angle for reflection of an EM wave is . The material is replaced by another material having refractive index , such that the critical angle at the interface between and materials is . If , , and , then is:
1
2
3
4
Official Solution
Correct Option: (1)
Using the relationship between critical angles and refractive indices, and applying Snell's law at the interface, we can derive the necessary expression for . The given condition helps in finding the value of . Thus, the correct expression for is .
28
PYQ 2025
hard
physicsID: jee-main
For the circuit shown above, the equivalent gate is:
1
AND gate
2
OR gate
3
NOT gate
4
NAND gate
Official Solution
Correct Option: (3)
Let's break down this logic circuit step by step to figure out the equivalent gate.
1. First Stage: The inputs and go into a NAND gate. The output of a NAND gate is the negation of the AND operation. So, the output here is:
2. Second Stage (Top): Input also goes into a NOT gate. The output of the NOT gate is the complement of the input, which is:
3. Third Stage (Top): The outputs from the first and second stages, and , are fed into an AND gate. The output of this AND gate is:
4. Second Stage (Bottom): Inputs and go into an OR gate. The output of an OR gate is:
5. Third Stage (Bottom): The output of the OR gate, , goes into a NOT gate. The output of this NOT gate is:
6. Final Stage: The outputs from the third stage (top) and the third stage (bottom), and , are fed into an OR gate. The final output is therefore:
Simplifying the Expression Using Boolean Algebra: Using De Morgan's Laws, we rewrite as . Substituting this into the expression for :
Distribute in the first term:
Simplify to :
Combine like terms:
Factor out :
Simplify to :
Final Answer: The equivalent gate for the given circuit is a NOT gate with input .
29
PYQ 2025
hard
physicsID: jee-main
Which of the following circuits has the same output as that of the given circuit?
1
2
3
4
Official Solution
Correct Option: (2)
The given Boolean logic circuit is shown below, and the corresponding solution is derived step by step.
P = A · B
Q = A · B
Y = P + Q = A · B + A · B
Y = A · (B + B)
Since B + B = B (idempotent law), we have:
Y = A · B
Y = A
The final output of the Boolean expression is:
Y = A
30
PYQ 2025
hard
physicsID: jee-main
The truth table for the circuit given below is: Choose the correct answer from the options given below:
1
2
3
4
Official Solution
Correct Option: (1)
The circuit involves a combination of AND and NOT gates, producing the output based on the inputs and . Looking at the truth table:
- For and , the output .
- For and , the output .
- For and , the output .
- For and , the output .
Thus, the truth table corresponds to the output as shown in option (1).
31
PYQ 2025
hard
physicsID: jee-main
Which of the following circuits has the same output as that of the given circuit?
1
A
2
B
3
C
4
D
Official Solution
Correct Option: (2)
This problem involves analyzing logic gates to find the circuit that produces the same output. Step 1: Analyze the given circuit. Identify the types of logic gates and their connections (AND, OR, NOT, etc.). Step 2: Write the logic expression for the output based on the given circuit. Step 3: Simplify the expression and compare it with the options provided. Final Conclusion:
The circuit corresponding to Option (2) produces the same output as the given circuit.
32
PYQ 2025
hard
physicsID: jee-main
To obtain the given truth table, the following logic gate should be placed at G
1
AND Gate
2
OR Gate
3
NOR Gate
4
NAND Gate
Official Solution
Correct Option: (3)
Step 1: Analyze the circuit structure. - The given circuit consists of two NOT gates applied to and , followed by two AND gates whose outputs feed into gate . - The final truth table indicates that is high for and , but low otherwise.
Step 2: Identify the logical expression. Observing the output pattern, we recognize it corresponds to the NOR operation:
Step 3: Select the appropriate gate. - The only logic gate that produces is the NOR Gate.
- Thus, the correct choice for gate is a NOR gate. Thus, the answer is .
33
PYQ 2025
medium
physicsID: jee-main
To obtain the given truth table, the following logic gate should be placed at G:
1
AND Gate
2
OR Gate
3
NOR Gate
4
NAND Gate
Official Solution
Correct Option: (3)
Step 1: Analyze the circuit structure. - The given circuit consists of two NOT gates applied to and , followed by two AND gates whose outputs feed into gate .
- The final truth table indicates that is high for and , but low otherwise. Step 2: Identify the logical expression. Observing the output pattern, we recognize it corresponds to the NOR operation: Step 3: Select the appropriate gate. - The only logic gate that produces is the NOR Gate.
- Thus, the correct choice for gate is a NOR gate. Thus, the answer is .
34
PYQ 2025
medium
physicsID: jee-main
The radiation pressure exerted by a 450 W light source on a perfectly reflecting surface placed at 2m away from it, is :
1
2
0
3
4
Official Solution
Correct Option: (3)
To determine the radiation pressure exerted by a light source on a perfectly reflecting surface, we can use the formula for radiation pressure on a reflecting surface:
where:
is the radiation pressure,
is the intensity of the light, and
is the speed of light, approximately .
First, we must calculate the intensity of the light at a distance 2 meters away from a point source with power 450 W. Intensity is given by the formula:
where:
is the power of the light source (450 W), and
is the area over which the power is spread, given by the surface area of a sphere: .
Since the distance , we have:
Substitute the values into the equation for intensity:
Calculating this, we get:
Now, we can calculate the radiation pressure:
Given that we have used approximations, the closest given option is:
Thus, the radiation pressure exerted by the 450 W light source is approximately .
This confirms the correct answer is:
.
35
PYQ 2025
easy
physicsID: jee-main
Choose the correct logic circuit for the given truth table having inputs A and B.
1
2
3
4
Official Solution
Correct Option: (2)
The problem asks us to identify the correct logic circuit from the given options that corresponds to the provided truth table for inputs A and B, and output Y.
Concept Used:
To solve this problem, we first need to determine the Boolean expression for the output Y based on the inputs A and B from the truth table. Then, for each of the given logic circuits, we will derive its corresponding Boolean expression. The correct circuit will be the one whose expression matches the one derived from the truth table.
The basic logic gates and their Boolean operations are:
OR gate: The output is 1 if at least one input is 1. Represented by . So, .
AND gate: The output is 1 only if all inputs are 1. Represented by . So, .
NOT gate (Inverter): The output is the inverse of the input. Represented by a bar over the variable. So, .
We will also use the absorption law of Boolean algebra: .
Step-by-Step Solution:
Step 1: Analyze the given truth table to find the Boolean expression for Y.
The truth table is:
A
B
Y
0
0
0
0
1
0
1
0
1
1
1
1
By observing the table, we can see that the output Y is 0 whenever the input A is 0, and the output Y is 1 whenever the input A is 1. The value of Y is independent of the input B. Therefore, the Boolean expression for the output is simply:
Step 2: Analyze each of the given logic circuits to find their Boolean expressions.
Circuit (1):
The inputs A and B go into an OR gate, giving the output . This output and the input B are then fed into an AND gate. The final output Y is:
Using the distributive law: . Using the absorption law, this simplifies to . This does not match .
Circuit (2):
The inputs A and B go into an OR gate, giving the output . This output and the input A are then fed into an AND gate. The final output Y is:
Using the distributive law: . Since , this becomes . Factoring out A gives . Since , the expression simplifies to:
This expression matches the expression derived from the truth table.
Circuit (3):
The inputs A and B go into an OR gate, giving . The input B is inverted to . These two results are fed into an AND gate. The final output Y is:
This expression is 1 only when A=1 and B=0, which does not match the truth table.
Circuit (4):
The inputs A and B go into an OR gate, giving . The input A is inverted to . These two results are fed into an AND gate. The final output Y is:
This expression is 1 only when A=0 and B=1, which does not match the truth table.
Final Computation & Result:
After analyzing all the circuits, only the circuit in option (2) produces the Boolean expression , which is consistent with the given truth table. Therefore, the correct logic circuit is option (2).
The correct option is (2).
36
PYQ 2025
medium
physicsID: jee-main
Consider the following logic circuit. The output is Y = 0 when :
1
A = 1 and B = 1
2
A = 0 and B = 1
3
A = 1 and B = 0
4
A = 0 and B = 0
Official Solution
Correct Option: (1)
To determine when the output for the given logic circuit, let's analyze the circuit step-by-step.
The circuit consists of an AND gate, an OR gate, and a NOT gate.
Inputs: A and B
The AND gate receives inputs A and the output of the NOT gate (which inverts B).
The OR gate receives inputs B and the output of the AND gate.
The final output Y is obtained by passing the output of the OR gate through another AND gate with input A.
Let's analyze the circuit logic:
The NOT gate inverts B, so if , the NOT gate outputs 1, and if , the NOT gate outputs 0.
The output of the AND gate is given by . This is 1 if and .
The output of the OR gate is . This is 1 if either or if both and .
The final AND gate gives output .
We need to determine when :
From the expression , becomes 0 only if .
However, if , the first input to the final AND gate is 0, making irrespective of the other term.
Examining the options, we find:
For :
NOT gate output:
AND gate output:
OR gate output:
Final AND gate output:
By verifying the calculations for all combinations, we find that the output when
Correct Option:
A = 1 and B = 1
37
PYQ 2025
medium
physicsID: jee-main
A particle oscillates along the -axis according to the law, , where and is the time period of oscillation. The kinetic energy ( ) of the particle as a function of is correctly represented by the graph:
1
2
3
4
Official Solution
Correct Option: (1)
The kinetic energy of a particle is given by: where is the velocity of the particle. The velocity is the derivative of the displacement with respect to time: Thus, the velocity is proportional to , and the kinetic energy is proportional to the square of the velocity, which results in a graph where the kinetic energy increases as the particle moves from the origin to its maximum displacement and decreases symmetrically thereafter. Final Answer: Graph 1.
38
PYQ 2026
medium
physicsID: jee-main
In the figure the LED will glow for input ( is low potential and is high potential).
1
2
3
4
Official Solution
Correct Option: (1)
Concept:
OR gate output is if any input is AND gate output is only if both inputs are LED glows when point is at higher potential than point Step 1: Write expressions for points and . From the circuit:
Step 2: Condition for LED to glow. Step 3: Check option (A): .
This gives correct polarity across LED for glowing as per circuit orientation. Step 4: Verify remaining options. Other combinations either give: Both and high, or No potential difference across LED Hence LED does not glow for them.
39
PYQ 2026
medium
physicsID: jee-main
For the given logic gate, find the output function.
1
2
3
4
Official Solution
Correct Option: (4)
Concept: To find the output of a logic circuit: Write the Boolean expression gate by gate Apply NOT operations carefully Use De Morgan’s laws for simplification Step 1: Analyze the upper branch. Inputs and go into an AND gate followed by a NOT gate. Step 2: Analyze the lower branch. Inputs and go into an OR gate. Step 3: Combine both branches. The outputs of the two branches go into an AND gate followed by a NOT gate. Step 4: Apply De Morgan’s theorem.
40
PYQ 2026
medium
physicsID: jee-main
Which logic gate is given in the figure?
1
XOR
2
NOR
3
NAND
4
OR
Official Solution
Correct Option: (3)
Step 1: Understanding the diagram. The given diagram represents a NAND gate. The NAND gate is the complement of the AND gate, and it produces a false output only when both inputs are true. Step 2: Analyzing the options. (1) XOR: This is incorrect. The XOR gate outputs true when the inputs are different. (2) NOR: This is incorrect. The NOR gate outputs true only when both inputs are false. (3) NAND: Correct — The NAND gate produces the opposite of an AND gate. It outputs false only when both inputs are true. (4) OR: This is incorrect. The OR gate outputs true if at least one input is true. Step 3: Conclusion. The correct answer is (3) NAND, as it correctly describes the logic gate in the diagram.