Chapter 7: Boolean Algebra | class 12th | mcqs of computer science

1. Boolean Algebra can be used to

• Simplify any algebraic expressions
• Minimize the number of switches in a circuits
• Solve the mathematical problem
• Perform arithmetic calculation

A. Simplify any algebraic expressions

2. An inverter gates can be developed using

• Two diodes
• A resistance and capacitance
• A transistor
• An inductance and capacitance

C. A transistor

3. if an input A is given to an inverter,the output will be

• 1/A
• 1
• A
• ‾A

D. ‾A

4. The output of two input OR gate is high

• . Only if both inputs are high
• Only if both inputs are low
• Only if one input is high and the other is low
• If at least one of the inputs is low

D. If at least one of the inputs is low

5. the output of a two input AND gate is high

• only if both the inputs are high
• only if both the inputs are low
• only if one inputs is high and other is low
• if atleast one of the input is low

A. only if both the inputs are high

6. NAND gate means

• inversion followed by And Gates
• AND gates followed by an inverter
• AND gate followed by an or gate
• None of these

B. AND gates followed by an inverter

7. The out put of two input NAND gate is high

• .only if both the inputs are high
• only if both the inputs are low
• only if one input is high and other input is low
• if atleast one the inputs is low

D. if atleast one the inputs is low

8. A NOT gate means

• Inversion followed by an OR gate
• OR gate followed by an an inverter
• Not gate followed by an OR gate
• NAND gate followed by an OR gate

B. OR gate followed by an an inverter

9. The output of two input NOR gate is high

• Only if both the inputs are high
• only if both the inputs are low
• only if one of the input is high and the other is low
• if atleast one the inputs is high

B. only if both the inputs are low

10. A Digital word has even parity

• if it has even number of 1s
• if it has even number of 0 s
• if the decimal value of word is even
• None of these

A. if it has even number of 1s

11. An XOR gate gives a high output

• if there are odd number of 1s in the input
• if these are even number of 1 s in the input
• .if there are odd number of 0s in the input
• if there are even numbers of 1 s in the input

A. if there are odd number of 1s in the input

12. An exclusive NOR gate is logically equal to

• inverter followed by an XOR gate
• NOT gate followed by an exclusive XOR gate
• Exclusive OR gate followed by an inverter
• Complement of a NOR gate

C. Exclusive OR gate followed by an inverter

13. De Morgan’s theorem states that

• ¯(A+B) = ¯A.¯B AND ¯(A.B) = ¯A.¯B
• ¯(A+B) = ¯A+¯B AND ¯(A.B) = ¯( A).¯B
• ¯( A+B)=¯( A).¯B AND ¯(A.B) = ¯A+¯B
• ¯( A+B) = ¯A+¯B AND ¯(A.B)= ¯A+¯B

C. ¯( A+B)=¯( A).¯B AND ¯(A.B) = ¯A+¯B

14. The logic expression AB+ (A.B) can be implemented by given inputs  And B to two input

• NOR gate
• Exclusive NOR gate
• Exclusive OR gate
• NAND gate

C. Exclusive OR gate

15. The logic expression AB+ ¯(A.B) can be implemented by given inputs A And B to two input

• NOR Gate
• Exclusive NOR gate
• Exclusive OR gate
• NAND Gate

B. Exclusive NOR gate

16. The gate ideally suited for bit comparison is a

• Two input exclusive NOR gate
• Two input exclusive OR gate
• Two input NAND date
• Two input NOR gate

A. Two input exclusive NOR gate

17. Two input Exclusive NOR gate gives high output

• when one input is high and the other is low
• only when the both the inputs are low
• when the both the inputs are same
• only when both the inputs are high

C. when the both the inputs are same