Question

What is a NOR gate? Draw its logic symbol and obtain the truth table.

Hint:

The NOR gate is a universal gate because any other logic gate can be implemented using just NOR gates.

Answer 1

NOR Gate

A NOR gate is a digital logic gate that outputs true (1) only when both of its inputs are false (0). It is the inverse of the OR gate.

Logic Symbol of NOR Gate:

The logic symbol of a NOR gate is the same as the OR gate with a small circle (representing NOT) at the output. The symbol for a 2-input NOR gate is:

\[ \text{NOR Gate Symbol} \]

Truth Table for NOR Gate:

The truth table for a 2-input NOR gate is:

\[ \begin{array}{|c|c|c|} \hline \text{Input A} & \text{Input B} & \text{Output (A NOR B)} \\ \hline 0 & 0 & 1 \\ 0 & 1 & 0 \\ 1 & 0 & 0 \\ 1 & 1 & 0 \\ \hline \end{array} \]

- When both inputs \(A\) and \(B\) are 0, the output is 1.

- In all other cases, the output is 0.