Question

Draw the truth table of a NOR gate.

Answer 1

Hint: The table which is used for the representation of the Boolean expression of a logic gate is known as a truth table. Boolean expression gives a relation between the input, output, and the logic (operation) used by the gate. There are three basic gates with the combination of which we can design different gates or complex digital systems.

Complete answer:
Gates is considered to be the building blocks of any digital system. That system uses binary signals (0 or 1). There can be more than one input pin but only a single output. As per the relation between the input and the output signals the truth table of different gates (logic gate) is formed.
The three main types of gates are AND gate, OR gate, NOT gate.
The combination of the OR gate and NOT gate is termed as the NOR gate.
The circuit of this combination can be visualized as in the diagram below,

The standard symbol used for the NOR gate is,

The OR gate is used for the addition of two coming inputs which can be solved mathematically using Bollens extension
$A+B=Y$
The NOT gate only has one input and one output pin. It is used to invert (compliment) the input signal,
$\bar{A}=Y$
So the combination of these two gates forms a logic gate which is popularly called NOR gate. So the Operation of the NOR gate will be complementing the sum of the two input signals.
This expression is written in Bollen's expression as shown below,
$\bar{A}+\bar{B}=Y$
So, the truth table of the NOR gate is given as,

A	B	Y (output)
0	0	1
0	1	0
1	0	0

Note:
The sign convention of the binary system is given as per the person's choice but the logic and operation of the system are always the same. In the real world, a single gate is very small so few gates are combined to form IC chips which are used in circuiting in the laboratory. All the gates in an IC are powered and grounded using common source and common ground.