Logic Gates MCQs Questions and Answers

Welcome to our blog post on Logic Gates MCQs Questions and Answers. In today’s digital world computer literacy has become essential for everyone. Whether you are a student, or a professional, it is important to have a good understanding of Logic Gates in Computer Science. To enhance your understanding of Logic Gates, we have prepared an exciting Multiple-Choice Questions (MCQ) quiz consisting of 30 very important questions and answers.

Top 30 Logic Gates MCQs Questions and Answers

Question 1. Which number system is used by digital computers?

1. Decimal
   
2. Binary
   
3. Octal
   
4. Hexadecimal
   

Answer: B

 

Question 2. What is the base of binary number system?

1. 2
   
2. 10
   
3. 8
   
4. 16
   

Answer: A

 

Question 3. Which number system has a base of 16?

1. Decimal
   
2. Binary
   
3. Octal
   
4. Hexadecimal
   

Answer: D

 

Question 4. How many bits are in a byte?

1. 4
   
2. 8
   
3. 16
   
4. 32
   

Answer: B

Question 5. Which of the following is a logic gate?

1. OR gate
   
2. XOR gate
   
3. NAND gate
   
4. All of the above
   

Answer: D

 

Question 6. Which of the following is a NOT gate?

1. AND gate
   
2. OR gate
   
3. XOR gate
   
4. None of the above
   

Answer: D

 

Question 7. Which of the following is a universal gate?

1. AND gate
   
2. OR gate
   
3. XOR gate
   
4. NAND gate
   

Answer: D

 

Question 8. Which of the following is a basic logic gate?

1. AND gate
   
2. XOR gate
   
3. NAND gate
   
4. All of the above
   

Answer: A

 

Question 9. What is the output of an AND gate?

1. 0
   
2. 1
   
3. Depends on the input
   
4. None of the above
   

Answer: C

 

Question 10. What is the output of an OR gate?

1. 0
   
2. 1
   
3. Depends on the input
   
4. None of the above
   

Answer: C

 

Question 11. What is the output of a NOT gate?

1. 0
   
2. 1
   
3. Depends on the input
   
4. None of the above
   

Answer: C

 

Question 12. Which of the following gates is equivalent to an OR gate followed by a NOT gate?

1. NAND gate
   
2. NOR gate
   
3. XOR gate
   
4. XNOR gate
   

Answer: B

 

Question 13. Which of the following gates is equivalent to an AND gate followed by a NOT gate?

1. NAND gate
   
2. NOR gate
   
3. XOR gate
   
4. XNOR gate
   

Answer: A

 

Question 14. What is the truth table for an AND gate?

1. 0 0 0 1
   0 1 0 1
   
2. 0 0 1 1
   0 1 1 1
   
3. 0 1 1 1
   1 0 0 0
   
4. 0 1 0 0
   1 0 1 1
   

Answer: C

 

Question 15. What is the truth table for an OR gate?

1. 0 0 0 1
   0 1 0 1
   
2. 0 0 1 1
   0 1 1 1
   
3. 0 1 1 1
   1 0 0 0
   
4. 0 1 0 0
   1 0 1 1
   

Answer: A

 

Logic Gates MCQs Questions and Answers

Question 16. What is the truth table for a NOT gate?

1. 0 1
   1 0
   
2. 0 0
   1 1
   
3. 1 0
   0 1
   
4. 1 1
   0 0
   

Answer: A

 

Question 17. Which of the following gates is equivalent to an XOR gate followed by a NOT gate?

1. NAND gate
   
2. NOR gate
   
3. XOR gate
   
4. XNOR gate
   

Answer: D

 

Question 18. What is the truth table for an XOR gate?

1. 0 0 0 1
   0 1 1 0
   
2. 0 0 1 1
   0 1 0 1
   
3. 0 1 1 0
   1 0 0 1
   
4. 0 1 0 0
   1 0 1 1
   

Answer: C

Question 19. Which of the following is a combinational logic circuit?

1. Flip-flop
   
2. Counter
   
3. Decoder
   
4. All of the above
   

Answer: C

 

Question 20. What is the purpose of a decoder?

1. To convert a binary code into a decimal number
   
2. To convert a decimal number into a binary code
   
3. To convert a binary code into a hexadecimal number
   
4. None of the above
   

Answer: A

 

Question 21. Which of the following is an example of a half adder?

1. AND gate
   
2. OR gate
   
3. XOR gate
   
4. None of the above
   

Answer: C

 

Question 22. What is the purpose of a full adder?

1. To perform addition of two binary numbers
   
2. To perform subtraction of two binary numbers
   
3. To perform multiplication of two binary numbers
   
4. None of the above
   

Answer: A

 

Question 23. Which of the following is an example of a multiplexer?

1. AND gate
   
2. OR gate
   
3. XOR gate
   
4. None of the above
   

Answer: D

 

Question 24. What is the purpose of a multiplexer?

1. To perform addition of two binary numbers
   
2. To select one of several input signals and forward the selected input to a single output line
   
3. To convert a binary code into a decimal number
   
4. None of the above
   

Answer: B

 

Question 25. Which of the following is an example of a demultiplexer?

1. AND gate
   
2. OR gate
   
3. XOR gate
   
4. None of the above
   

Answer: D

 

Question 26. What is the purpose of a demultiplexer?

1. To perform addition of two binary numbers
   
2. To select one of several input signals and forward the selected input to a single output line
   
3. To convert a binary code into a decimal number
   
4. None of the above
   

Answer: B

 

Question 27. Which of the following is an example of a flip-flop?

1. AND gate
   
2. OR gate
   
3. XOR gate
   
4. None of the above
   

Answer: D

 

Question 28. What is the purpose of a flip-flop?

1. To perform addition of two binary numbers
   
2. To store a single bit of information
   
3. To convert a binary code into a decimal number
   
4. None of the above
   

Answer: B

 

Question 29. What is the output of an XNOR gate?

1. 0
   
2. 1
   
3. Depends on the input
   
4. None of the above
   

Answer: B

 

Question 30. What is the truth table for an XNOR gate?

1. 0 0 1 0
   0 1 0 1
   
2. 0 0 1 1
   0 1 1 0
   
3. 0 1 0 1
   1 0 1 0
   
4. 0 1 1
   

Answer: A

In conclusion, these 30 multiple choice questions cover various topics related to logic gates in computer science. It is important to have a good understanding of these concepts as they form the foundation of digital electronics and computing. By practicing these questions, you can test your knowledge and identify areas where you need more study. Remember to always read the questions carefully and choose the best possible answer.

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