Question
Question: When the inputs of a two input logic gate are 0 and 0, the output is 1. When the inputs are 1 and 0 ...
When the inputs of a two input logic gate are 0 and 0, the output is 1. When the inputs are 1 and 0 the output is 0. The logic gate is the type
A. AND
B. NAND
C. NOR
D. OR
Solution
Learn the definition of the basic logic gates. Study about the different types of logic gates. From the truth table of the logic gates find the solution to the problem.Logic gates are an important concept if you are studying electronics. These are important digital devices that are mainly based on the Boolean function.
Complete answer:
We know there are mainly three types of basic logic gates.
1. AND gate
2. OR gate
3. Not gate
AND gate: AND gate is one of the basic logic gates in which if we put all the inputs high state the gate gives a high output state. So, in AND gate output will only be high state when all the inputs are high else it will give a low state at output.
OR gate: OR gate is the basic type of gate in which if we put any of the input states high the output of the gate gives a high state. So, in or gate one high state at input gives a high output. It only gives low input when all the inputs are low state.
NOT gate: NOT gate is a basic gate in which the output is a complement of the input means a high input state gives a low output state and a low input state gives a high output.
NAND and NOR gate are the combination of AND, NOT and OR, NOT gate respectively.
The truth table of two input gates are given in the table:
| Input 1 | Input 2 | OR | AND | NOR | NAND |
|---|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 1 | 1 |
| 0 | 1 | 1 | 0 | 0 | 1 |
| 1 | 0 | 1 | 0 | 0 | 1 |
| 1 | 1 | 1 | 1 | 0 | 0 |
Now, we have given here a two input gate in which all the inputs are low 0,0 and the output is high-1.Now, we know that for OR and AND gate all low inputs give a low output but in NAND and NOR gate all low input-0 gives a high output-1 .Hence, the gate must be NAND or NOR gate. Now, when inputs are 1 and 0 the output is 0. For, NAND gate output is 0 only when the inputs are high (1 and 1) but for NOR the input is 0 for at least one high input.Hence, the gate is a NOR type gate.
Hence, option C is the right answer.
Note: To solve this type of problem learn the definition and the truth table of the gates well. Using the truth table or definition we can easily differentiate the gates for various combinations of inputs and outputs. NOT is a one input gate while other gates are more than one input gate.