Which description correctly identifies a NOT gate?

Which description correctly identifies a NOT gate?

• A. Returns the sum of inputs
• B. Inverts the input
• C. Reverses the order of inputs
• D. Outputs true when any input is true

Answer: (B)

A NOT gate performs logical negation. It has a single input and outputs the opposite value: if the input is 0, the output is 1, and if the input is 1, the output is 0. This makes the description "inverts the input" the best match. The other ideas describe different operations: summing inputs would be addition (or an adder), reversing the order of inputs isn’t how a NOT gate operates, and outputting true when any input is true is the behavior of an OR gate.

A NOT gate performs logical negation. It has a single input and outputs the opposite value: if the input is 0, the output is 1, and if the input is 1, the output is 0. This makes the description "inverts the input" the best match. The other ideas describe different operations: summing inputs would be addition (or an adder), reversing the order of inputs isn’t how a NOT gate operates, and outputting true when any input is true is the behavior of an OR gate.