Question

Consider the following logic circuit.

The output Y is LOW when:

• A. A is HIGH and B is LOW
• B. A is LOW and B is HIGH
• C. Both A and B are LOW
• D. Both A and B are HIGH

Answer 1

The Correct Option is A

This logic circuit contains a NOT gate followed by an AND gate. The NOT gate inverts input \( A \), and the AND gate takes both inputs (inverted \( A \) and \( B \)).

The output \( Y \) will be LOW only when the combination of inputs results in a LOW output from the AND gate.

Key Observation:

- For an AND gate to output LOW, at least one of the inputs must be LOW.

- Therefore, when \( A \) is HIGH and \( B \) is LOW, the NOT gate will make \( A \) LOW, and the AND gate will output LOW.

Conclusion:

Thus, the correct answer is (A): A is HIGH and B is LOW.