NEET2026PhysicsChapterActual
Which of the following truth tables correctly represents the final output Y of the given logic circuit?
Options
- AA B Y 0 0 1 0 1 0 1 0 1 1 1 1
- BA B Y 0 0 0 0 1 1 1 0 0 1 1 0
- CA B Y 0 0 1 0 1 1 1 0 1 1 1 0
- DA B Y 0 0 0 0 1 1 1 0 1 1 1 1
Correct answer
A. A B Y 0 0 1 0 1 0 1 0 1 1 1 1
Step-by-step solution
The circuit consists of three logic gates: 1. A NAND gate with inputs A and B . Its output is Y₁ = A B . 2. An AND gate with inputs Y₁ and B . Its output is Y₂ = Y₁ B = ( A B ) B . 3. A NOR gate with both inputs connected to Y₂ . This acts as a NOT gate. Its output is Y = Y₂ + Y₂ = Y₂ . Now, simplify the Boolean expression for Y : Y₂ = ( A B ) B Using De Morgan's law, A B = A + B . Y₂ = ( A + B ) B = A B + B B Since B B = 0 , we have Y₂ = A B . The final output is Y = Y₂ = A B . Using De Morgan's law again: Y = A +