Consider the NAND logic function. The output of a NAND gate goes LOW only in the single case when every one of its inputs is HIGH. Evaluate the statement.

Difficulty: Easy

Correct Answer: Correct

Explanation:

Introduction / Context:A NAND gate is the logical negation of AND. Understanding its truth condition for a LOW output is foundational for digital design and troubleshooting.

Given Data / Assumptions:

  • NAND is defined as NOT(AND).
  • Inputs can be 0 or 1; output depends on all inputs.

Concept / Approach:Since AND outputs 1 only when all inputs are 1, NAND will output 0 exactly in that same case (because it inverts the AND result). Otherwise, NAND outputs 1.

Step-by-Step Solution:1) For all inputs = 1, AND = 1, so NAND = 0.2) If any input = 0, AND = 0, so NAND = 1.3) Therefore, “LOW only if all inputs are HIGH” is correct.

Verification / Alternative check:Construct a two-input truth table to verify the unique LOW case (1,1).

Why Other Options Are Wrong:“Incorrect” and claims about LOW on mixed or any 0 contradict the definition of NAND.

Common Pitfalls:Confusing NAND with NOR or with AND; forgetting that NAND inverts the AND output.

Final Answer:Correct

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