MCQ IN COMPUTER SCIENCE & ENGINEERING

Detailed explanation-1: -NAND gate is called universal gate because all other logic gates such as AND, OR and NOT can be constructed from various combinations of NAND gates. Thus, any digital circuit can be made by appropriate repetitive use of NAND gate.

Detailed explanation-2: -Since the NAND gate is a universal gate, we can convert any circuit into a circuit consisting only of NAND gates.

Detailed explanation-3: -The NAND gate or “NotAND” gate is the combination of two basic logic gates, the AND gate and the NOT gate connected in series. The NAND gate and NOR gate can be called the universal gates since the combination of these gates can be used to accomplish any of the basic operations.

Detailed explanation-4: -A universal gate is a gate which can implement any Boolean function without need to use any other gate type. The NAND and NOR gates are universal gates. In practice, this is advantageous since NAND and NOR gates are economical and easier to fabricate and are the basic gates used in all IC digital logic families.

Detailed explanation-5: -For this purpose we use three NAND gate in manner as shown. The first two NAND gates are operated as NOT gates and their outputs are fed to the third. The resulting circuit is OR gate.