Which one of the given options is the correct sequence of outputs to complete the truth...
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Which one of the given options is the correct sequence of outputs to complete the truth table if A and B are inputs for a 2-input 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 given rows: (1,0)→1, (0,1)→1, (1,1)→0, (0,0)→1, yielding the sequence 1101. Wait—let me recalculate: The sequence should be read as outputs in order of the rows given: Row 1 (A=1, B=0) outputs 1; Row 2 (A=0, B=1) outputs 1; Row 3 (A=1, B=1) outputs 0; Row 4 (A=0, B=0) outputs 1. This gives 1101, which is option B. However, let me verify the standard NAND truth table to ensure correctness.
Step-by-step Derivation:
NAND truth table (standard):
- A=0, B=0 → Output = 1 (NOT(0 AND 0) = NOT(0) = 1)
- A=0, B=1 → Output = 1 (NOT(0 AND 1) = NOT(0) = 1)
- A=1, B=0 → Output = 1 (NOT(1 AND 0) = NOT(0) = 1)
- A=1, B=1 → Output = 0 (NOT(1 AND 1) = NOT(1) = 0)
For the given rows in order:
- A=1, B=0: NAND(1,0) = 1
- A=0, B=1: NAND(0,1) = 1
- A=1, B=1: NAND(1,1) = 0
- A=0, B=0: NAND(0,0) = 1
Sequence: 1, 1, 0, 1 → "1101"