NOT gate outputs a high when the input is false.

NOT gate outputs a high when the input is false.

• A. Nand Gate
• B. Or Gate
• C. Not Gate
• D. And Gate

Answer: (C)

The main idea is that a NOT gate, or inverter, flips the logic level of its input. If you feed it a false signal (0), it outputs a true signal (1), which is a high level. In other words, 0 becomes 1 and 1 becomes 0 with a NOT gate. Its truth table is straightforward: input 0 gives output 1, input 1 gives output 0. The other gates don’t match this behavior for a false input. An OR gate would not produce a high when the input is false, since OR outputs high only when at least one input is high. An AND gate also wouldn’t—its output is high only when all inputs are high. A NAND gate is the negation of AND, and while it can produce a high for a false input in some configurations, the direct and defining action described (outputting a high when the input is false) points to the inverter as the correct, simplest explanation.

The main idea is that a NOT gate, or inverter, flips the logic level of its input. If you feed it a false signal (0), it outputs a true signal (1), which is a high level. In other words, 0 becomes 1 and 1 becomes 0 with a NOT gate. Its truth table is straightforward: input 0 gives output 1, input 1 gives output 0.

The other gates don’t match this behavior for a false input. An OR gate would not produce a high when the input is false, since OR outputs high only when at least one input is high. An AND gate also wouldn’t—its output is high only when all inputs are high. A NAND gate is the negation of AND, and while it can produce a high for a false input in some configurations, the direct and defining action described (outputting a high when the input is false) points to the inverter as the correct, simplest explanation.