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Saturday, 31 October

JEE Main 2021 · PhysicsMultiple choiceDiagram basedMediumDiagram reading

JEE Main 17 March 2021, Shift 2, Physics Q15

Question 15 of 90 in this shift, Physics question 15 of 30, Section A.

Which one of the following will be the output of the given circuit ?

The figure, in words

Logic circuit with inputs A and B and output Y. Input A feeds an AND gate and, through a vertical branch line, one input of an OR gate; input B feeds the other input of the OR gate and, through a vertical branch line (crossing the A branch with a small hop-over), the other input of the same AND gate. The AND gate output goes through a NOT gate (triangle with a small circle) to one input of a final AND gate; the OR gate output goes to the other input of the final AND gate, whose output is Y.
  1. (1)AND Gate
  2. (2)NAND Gate
  3. (3)XOR GateOfficial answer
  4. (4)NOR Gate

Official answer

Option 3

NTA final key.

Chapter
Semiconductor Electronics: Materials, Devices and Simple Circuits
Topic
Logic Gates
Idea tested
Combinational Logic Circuits

Same idea in other shifts

Asked 31× in all
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  2. 4 Apr 2026, Shift 1 · Q38Two 44 bits binary numbers, A=1101A=1101 and B=1010B=1010 are given in the inputs of a logic circuit shown in figure below. The output (YY) will…EasyDiagram basedHas a figure
  3. 5 Apr 2026, Shift 1 · Q45For the given logic circuit, which of the following inputs combination will make both LED-1 and LED-2 to glow?EasyDiagram basedHas a figure
  4. 6 Apr 2026, Shift 2 · Q43Refer to the logic circuit given below. For two inputs (A=1A=1, B=1B=1) and (A=0A=0, B=1B=1), output (YY) will be __________.EasyDiagram basedHas a figure
  5. 2 Apr 2025, Shift 2 · Q39In the digital circuit shown in the figure, for the given inputs the P and Q values are :MediumDiagram basedHas a figure
  6. 3 Apr 2025, Shift 1 · Q45Choose 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 basedHas a figure
  7. 3 Apr 2025, Shift 2 · Q45The truth table corresponding to the circuit given below is :EasyDiagram basedHas a figure
  8. 7 Apr 2025, Shift 2 · Q45Consider the following logic circuit. The output is Y=0Y=0 when :EasyDiagram basedHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.