# Boolean Algebra MCQ

## Boolean Algebra MCQ

Boolean Algebra MCQ, Objectives on Boolean Algebra, Multiple Choice Questions on Boolean Algebra, De Morgan’s theorem MCQ, Engineering MCQ, Digital Electronics MCQ,

MCQ on Combinational Logic Circuits

Flip-Flop MCQ

### Objective Type Questions

Q.1. A + AB + ABC + ABCD + ABCDE + …… =

• A
• A+ AB
• AB

Q.2. $A+\bar{A}B+\bar{A}\bar{B}C+\bar{A}\bar{B}\bar{C}D+....=$

• A+B+C+….
• $\bar{A}+\bar{B}+\bar{C}+\bar{D}+....=$
• 1
• 0

Q.3. De Morgan’s theorem states that

• $\bar{A+B}=\bar{A}\bar{B}$ and $\bar{AB}=\bar{A}+\bar{B}$
• $\bar{A+B}=\bar{A}+\bar{B}$ and $\bar{AB}=\bar{A}\bar{B}$
• $\bar{A+B}=A+B$ and $\bar{AB}=AB$
• $\bar{A+B}=\bar{A}\bar{B}$ and $\bar{AB}=\bar{A}\bar{B}$

Answer: $\bar{A+B}=\bar{A}\bar{B}$ and $\bar{AB}=\bar{A}+\bar{B}$

Q.4. The logic expression $(A+B)(\bar{A}+\bar{B})$ can be implemented by giving the inputs A and B to a two-input

• NOR gate
• NAND gate
• X-OR gate
• X-NOR gate

Q.5. The logic expression $(\bar{A}+B)(A+\bar{B})$ can be implemented by giving the inputs A and B to a two-input

• NOR gate
• NAND gate
• X-OR gate
• X-NOR gate

Q.6. Which of the following Boolean algebraic expressions is incorrect?

• $A+\bar{A}B=A+B$
• $A+AB=B$
• $(A+B)(A+C)=A+BC$
• $(A+\bar{B})(A+B)=A$

Answer: $A+AB=B$

Q.7. The simplified form of the Boolean expression (X + Y + XY)(X + Z) is

• X+Y+Z
• XY + YZ
• X + YZ
• XZ + Y

Q.8. The simplified form of the Boolean expression $(X+\bar{Y}+Z)(X+\bar{Y}+\bar{Z})(X+Y+Z)$ is

• $\bar{X}Y+Z$
• $X+\bar{Y}Z$
• $\bar{X}Y+\bar{Z}$
• $XY+\bar{Z}$

Answer: $X+\bar{Y}Z$

Q.9. A + B = B + A; AB = BA represent which laws?

• Commutative
• Associative
• Distributive
• Idempotence

Q.10. (A + B) + C = A + (B + C); (AB)C = A(BC) represent which laws?

• Commutative
• Associative
• Distributive
• Idempotence

Q.11. A(B + C) =AB + AC; A + BC = (A + B)(A + C) represent which laws?

• Commutative
• Associative
• Distributive
• Idempotence

Q.12. A + AB = A; A(A + B) = A represent which laws?

• Idempotence
• Absorption
• Associative
• Commutative

Q.13. $AB+\bar{A}C+BC=AB+\bar{A}C$ represents which theorem?

• Consensus
• Transposition
• De Morgan’s
• None of these

Q.14. $AB+\bar{A}C=(A+C)+(\bar{A}+B)$ represents which theorem

• Consensus
• Transposition
• De Morgan
• Included factor

Q.15. The dual of a Boolean expression is obtained by

• interchanging all 0s and 1s
• interchanging all 0s and 1s, all + and ‘.’ signs
• interchanging all 0s and 1s, all + and ‘.’ signs and complementing all the variables
• interchanging all + and ‘.’ signs and complementing all the variables

Answer: interchanging all 0s and 1s, all + and ‘.’ signs

Q.16. The complement of a Boolean expression is obtained by

• interchanging all 0s and 1s
• interchanging all 0s and 1s, all + and ‘.’ signs
• interchanging all 0s and 1s, all + and ‘.’ signs and complementing all the variables
• interchanging all + and ‘.’ signs and complementing all the variables

Answer: interchanging all 0s and 1s, all + and ‘.’ signs and complementing all the variables

Q.17. The logic expression $F=AB+\bar{B}C+AC$ is in

• SOP form
• POS form
• standard SOP form
• standard POS form

Q.18. The logic expression $F=(A+B+C)(A+\bar{C})(B+\bar{C})(A+C)$ is in

• SOP form
• POS form
• standard SOP form
• standard POS form

Q.19. K-map is used

• to minimize the number of flip-flops in a digital circuit
• to minimize the number of gates only in a digital circuits
• to minimize the number of gates and the fan in requirements of the gates in a digital circuit
• to design gates

Answer: to minimize the number of gates and the fan in requirements of the gates in a digital circuit

Q.20. The number of cells in a 6- variable K-map is

• 6
• 12
• 36
• 64