Logic Gates & Digital Electronics MCQs
Logic Gates & Digital Electronics MCQs
Class: CBSE Class 12 | Subject: Physics
Section 9: Electronic Devices
Topic: Logic Gates & Digital Electronics
Based on CBSE Board Examination Pattern
Section 9: Electronic Devices
Topic: Logic Gates & Digital Electronics
Based on CBSE Board Examination Pattern
Instructions: These Multiple Choice Questions (MCQs) are designed strictly as per the NCERT syllabus, making them ideal for CBSE Class 12 Board Examination preparation.
1. Digital electronics deals with signals which are:
Answer: B
Digital systems operate on discrete binary values (0 and 1).
Digital systems operate on discrete binary values (0 and 1).
2. Basic logic gates are:
Answer: A
These are fundamental building blocks of digital circuits.
These are fundamental building blocks of digital circuits.
3. AND gate output is 1 when:
Answer: B
Logical multiplication operation.
Logical multiplication operation.
4. OR gate performs logical:
Answer: A
Output 1 if any input is 1.
Output 1 if any input is 1.
5. NOT gate is also called:
Answer: A
It reverses input logic.
It reverses input logic.
6. NAND gate =
Answer: A
Universal gate.
Universal gate.
7. NOR gate =
Answer: A
Another universal gate.
Another universal gate.
8. Universal gates:
Answer: C
Can implement any logic circuit.
Can implement any logic circuit.
9. XOR gate output 1 when inputs are:
Answer: B
Exclusive OR operation.
Exclusive OR operation.
10. XNOR gate is:
Answer: A
Outputs 1 when inputs equal.
Outputs 1 when inputs equal.
11. Binary system base:
Answer: A
Uses digits 0 & 1.
Uses digits 0 & 1.
12. Decimal 5 in binary:
Answer: A
5 = 101₂.
5 = 101₂.
13. Boolean algebra introduced by:
Answer: A
George Boole developed logic algebra.
George Boole developed logic algebra.
14. De Morgan’s theorem relates:
Answer: A
Important simplification laws.
Important simplification laws.
15. Flip‑flop stores:
Answer: B
Basic memory element.
Basic memory element.
16. Half adder adds:
Answer: B
Produces sum & carry.
Produces sum & carry.
17. Logic 1 represents:
Answer: B
High voltage level.
High voltage level.
18. Simplification reduces:
Answer: D
Improves circuit efficiency.
Improves circuit efficiency.
19. Karnaugh map used for:
Answer: B
Graphical logic minimization.
Graphical logic minimization.
20. Digital circuits operate on:
Answer: B
Use binary number system.
Use binary number system.