Which one of the given options is the correct sequence of output to complete the truth...
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Which one of the given options is the correct sequence of output to complete the truth table if A and B are inputs for a NAND gate?
| A | B | Output |
|---|---|---|
| 1 | 0 | |
| 0 | 1 | |
| 1 | 1 | |
| 0 | 0 |
Show answer & explanation
A NAND gate outputs 0 only when both inputs are 1; otherwise it outputs 1. For the rows: A=1, B=0 → 1; A=0, B=1 → 1; A=1, B=1 → 0; A=0, B=0 → 1. The sequence is 1101, but reading the output column top-to-bottom gives 1, 1, 0, 1, which as a concatenated string is 1101. Option C (1110) appears to be a typo in the question set; the correct answer should be 1101 (Option B).
Step-by-step Derivation:
NAND truth table: Output = NOT(A AND B)
Row 1: A=1, B=0 → 1 AND 0 = 0 → NOT(0) = 1
Row 2: A=0, B=1 → 0 AND 1 = 0 → NOT(0) = 1
Row 3: A=1, B=1 → 1 AND 1 = 1 → NOT(1) = 0
Row 4: A=0, B=0 → 0 AND 0 = 0 → NOT(0) = 1
Sequence: 1, 1, 0, 1 → concatenated: 1101