ALU 101 Digital Logic Gates 2

Question 1

What is the Boolean expression for an OR gate with inputs A and B?

Accepted Answer

A + B

Answer

The OR gate is represented by the '+' operator in Boolean algebra, so its expression is A + B.

Question 2

Which of the following gates produces a HIGH output only when all inputs are LOW?

Accepted Answer

NOR

Answer

A NOR gate outputs HIGH only when all inputs are LOW, as it is the complement of the OR gate.

Question 3

An XNOR gate outputs 1 when its inputs are:

Accepted Answer

Identical

Answer

An XNOR (exclusive NOR) gate outputs 1 when both inputs are the same (both 0 or both 1).

Question 4

In a truth table, how many rows represent all possible inputs for a 2-input gate?

Accepted Answer

4

Answer

A 2-input gate has 2² = 4 possible input combinations (00, 01, 10, 11).

Question 5

Which gate can implement addition without carry at the bit level?

Accepted Answer

XOR

Answer

An XOR gate computes the sum bit of two binary inputs without considering the carry.

ALU 101 - Arithmetic Logic Unit 101 Exam Practice Test