Which of the following statement(s) is/are correct regarding AND logic gate?…
2024
Which of the following statement(s) is/are correct regarding AND logic gate? I. The AND gate produces the output value 1 if input A and input B are both equal to 1. II. The algebraic operation symbol of the AND function is the same as the multiplication symbol of ordinary arithmetic.
- A.
Neither I nor II
- B.
Only I
- C.
Both I and II
- D.
Only II
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Correct answer: C
A logic AND gate outputs HIGH (1) only when every one of its inputs is HIGH (1); if even one input is LOW (0), the output stays LOW (0). Multiplying two binary digits (0 or 1) gives exactly this same result — 1 times 1 is 1, and any 0 in the multiplication gives 0 — so Boolean algebra writes the AND operation using the same symbol as arithmetic multiplication, usually a dot, as in Y = A dot B.
For a 2-input AND gate with inputs A and B, the complete truth table is:
Input A | Input B | Output Y |
|---|---|---|
0 | 0 | 0 |
0 | 1 | 0 |
1 | 0 | 0 |
1 | 1 | 1 |
Only the last row gives Y = 1, exactly when A = 1 and B = 1 together — this is precisely the behaviour described in Statement I. And since Boolean AND behaves identically to arithmetic multiplication on 0/1 values, writing it with the multiplication dot, as in Y = A dot B, is the standard algebraic convention — this is precisely what Statement II describes.
"Neither I nor II" would need both claims to fail — but the truth table above and the standard multiplication-dot notation each independently hold, so this combination does not fit.
"Only I" would need the notation claim to fail — but Boolean AND is conventionally written with the same dot notation as multiplication, so this combination does not fit either.
"Only II" would need the truth-table claim to fail — but the truth table above shows output 1 only for the all-1 row, so this combination does not fit either.
Since both claims independently hold up against the truth table and the standard algebraic notation, the combination naming both of them is the one that fits.