Test 20
1. What is the hexadecimal equivalent of the binary number 1101?
a) D
b) 1D
c) 13
d) 1B
2. Which logic gate has an output that is true only if both inputs are true?
a) AND
b) OR
c) NOT
d) XOR
3. What is the octal equivalent of the binary number 1011?
a) 5
b) 7
c) 11
d) 13
4. What does TTL stand for in digital electronics?
a) Transistor-Transistor Logic
b) Time to Live
c) True Table Lookup
d) Triode Transition Logic
5. How many bits are typically in a nibble?
a) 2
b) 4
c) 8
d) 16
6. Which logic gate has an output that is true if and only if exactly one of its inputs
is true?
a) AND
b) OR
c) NOT
d) XOR
7. What does CMOS stand for in digital electronics?
a) Complementary Metal Oxide Semiconductor
b) Computer Mainframe Operating System
c) Central Memory Organization System
d) Current Mode Operation System
8. In digital electronics, what is a flip-flop?
a) A type of logic gate
b) A device used for analog-to-digital conversion
c) A circuit element that stores state information
d) A component used for power regulation
9. Which type of logic gate outputs true if and only if all its inputs are false?
a) AND
b) OR
c) NAND
d) NOR
10. What is the main advantage of using binary representation in digital systems?
a) Simplifies programming
b) Allows for easier debugging
c) Facilitates high-speed calculations
d) Reduces circuit complexity
11. What is the purpose of a multiplexer (MUX) in digital electronics?
a) To convert analog signals to digital
b) To combine multiple signals into one
c) To store data temporarily
d) To generate clock signals
12. What is the function of a decoder in digital circuits?
a) Converts binary data to analog signals
b) Transforms digital signals into audio
c) Deciphers encrypted messages
d) Converts binary data to a specific set of outputs
13. Which logic gate has an output that is the inverse of its input?
a) AND
b) OR
c) NOT
d) XOR
14. What is the hexadecimal equivalent of the binary number 1010?
a) A
b) B
c) C
d) D
15. What is the role of a counter in digital electronics?
a) To generate clock signals
b) To store data for later retrieval
c) To count the number of pulses
d) To decode binary data
16. In digital systems, what is the function of an adder circuit?
a) Performs arithmetic addition
b) Converts analog to digital signals
c) Modifies clock signals
d) Implements error correction
17. What is the purpose of a register in digital electronics?
a) Stores binary data temporarily
b) Generates high-frequency signals
c) Converts digital signals to analog
d) Performs logic operations
18. Which logic gate outputs true if and only if all its inputs are true?
a) AND
b) OR
c) NOT
d) XOR
19. What is the primary function of a shift register?
a) Converts analog signals to digital
b) Stores data and shifts it sequentially
c) Multiplies binary numbers
d) Divides clock pulses evenly
20. What is the purpose of a comparator in digital systems?
a) Converts digital signals to analog
b) Compares two binary numbers
c) Generates random numbers
d) Filters out noise from signals
21. In digital electronics, what does the term "clock cycle" refer to?
a) The time taken to execute a program
b) The rate at which binary digits are transmitted
c) The number of logic gates in a circuit
d) The interval between two successive clock pulses
22. What does ALU stand for in digital computers?
a) Analog Logic Unit
b) Arithmetic and Logic Unit
c) Automated Learning Unit
d) Algorithmic Language Utility
23. Which component is responsible for storing instruction sets in a digital
computer?
a) RAM
b) ROM
c) CPU
d) GPU
24. What is the primary role of a multiplexer (MUX) in digital systems?
a) To increase signal amplitude
b) To select one of many inputs and pass it to the output
c) To convert digital signals to analog
d) To amplify audio signals
25. What is the function of a demultiplexer in digital electronics?
a) Combines multiple signals into one
b) Decodes binary data into ASCII characters
c) Divides one signal into multiple outputs
d) Detects errors in data transmission
26. Which logic gate has an output that is true if and only if both inputs are false?
a) AND
b) OR
c) NOT
d) NOR
27. What is the purpose of a flip-flop in digital circuits?
a) To convert analog signals to digital
b) To store one bit of binary data
c) To amplify electrical signals
d) To generate clock pulses
28. In digital systems, what does the term "bus" refer to?
a) A group of wires carrying related signals
b) A storage unit for data retrieval
c) A component that converts digital to analog signals
d) A device that measures clock frequency
29. What is the role of an encoder in digital electronics?
a) Converts analog signals to digital
b) Converts binary data into a specific code
c) Combines multiple signals into one
d) Stores data temporarily
30. Which logic gate outputs true if and only if one input is true and the other is
false?
a) AND
b) OR
c) NOT
d) XOR
31. What is the primary function of a counter in digital systems?
a) To store data temporarily
b) To generate clock signals
c) To count the number of pulses
d) To amplify electrical signals
32. What is the purpose of a multiplexer (MUX) in digital circuits?
a) To convert analog signals to digital
b) To combine multiple signals into one
c) To store data temporarily
d) To generate clock signals
33. Which type of logic gate outputs true if and only if at least one of its inputs is
false?
a) AND
b) OR
c) NAND
d) NOR
34. What does CMOS stand for in digital electronics?
a) Complementary Metal Oxide Semiconductor
b) Computer Memory Organization System
c) Central Management Operating System
d) Current Mode Operating System
35. In digital electronics, what is a flip-flop?
a) A type of logic gate
b) A device used for analog-to-digital conversion
c) A circuit element that stores state information
d) A component used for power regulation
36. Which logic gate has an output that is true only if both of its inputs are true?
a) AND
b) OR
c) NOT
d) XOR
37. What is the binary equivalent of the decimal number 47?
a) 101101
b) 101111
c) 110111
d) 111101
38. Which logic gate is represented by the Boolean expression \( \overline{A}
\cdot B \)?
a) AND
b) OR
c) NAND
d) XOR
39. What is the octal equivalent of the binary number 110010?
a) 62
70
b) 62
39
c) 62
d) 56
62
40. What is the primary purpose of a decoder in digital electronics?
a) Converts binary data to analog signals
b) Transforms digital signals into audio
c) Deciphers encrypted messages
d) Converts binary data to a specific set of outputs
Test 20
Explanation
1. What is the hexadecimal equivalent of the binary number 1101?
o Correct Answer: a) D
o Explanation: Binary 1101 converts to hexadecimal D. In binary, 1101 is equal to
8+4+1=138 + 4 + 1 = 138+4+1=13, which is D in hexadecimal.
2. Which logic gate has an output that is true only if both inputs are true?
o Correct Answer: a) AND
o Explanation: The AND gate outputs true only when both of its inputs are true.
3. What is the octal equivalent of the binary number 1011?
o Correct Answer: d) 13
o Explanation: Binary 1011 converts to octal 13. Group the binary digits in sets of
three from the right (001 011), where 001 is 1 and 011 is 3 in octal.
4. What does TTL stand for in digital electronics?
o Correct Answer: a) Transistor-Transistor Logic
o Explanation: TTL stands for Transistor-Transistor Logic, a type of digital logic
family.
5. How many bits are typically in a nibble?
o Correct Answer: b) 4
o Explanation: A nibble consists of 4 bits.
6. Which logic gate has an output that is true if and only if exactly one of its inputs is
true?
o Correct Answer: d) XOR
o Explanation: The XOR (exclusive OR) gate outputs true only when exactly one of
its inputs is true.
7. What does CMOS stand for in digital electronics?
o Correct Answer: a) Complementary Metal Oxide Semiconductor
o Explanation: CMOS stands for Complementary Metal Oxide Semiconductor, a
technology used in integrated circuits.
8. In digital electronics, what is a flip-flop?
o Correct Answer: c) A circuit element that stores state information
o Explanation: A flip-flop is a circuit element used to store binary data, typically
one bit.
9. Which type of logic gate outputs true if and only if all its inputs are false?
o Correct Answer: d) NOR
o Explanation: The NOR gate outputs true only when all its inputs are false.
10. What is the main advantage of using binary representation in digital systems?
o Correct Answer: d) Reduces circuit complexity
o Explanation: Binary representation simplifies circuit design because it only
requires two states, making logic circuits less complex.
11. What is the purpose of a multiplexer (MUX) in digital electronics?
o Correct Answer: b) To combine multiple signals into one
o Explanation: A multiplexer (MUX) selects one of many input signals and passes
it to the output.
12. What is the function of a decoder in digital circuits?
o Correct Answer: d) Converts binary data to a specific set of outputs
o Explanation: A decoder translates binary input data into a specific output signal
pattern.
13. Which logic gate has an output that is the inverse of its input?
o Correct Answer: c) NOT
o Explanation: The NOT gate outputs the inverse of its input.
14. What is the hexadecimal equivalent of the binary number 1010?
o Correct Answer: a) A
o Explanation: Binary 1010 converts to hexadecimal A. In binary, 1010 is equal to
8+2=108 + 2 = 108+2=10, which is A in hexadecimal.
15. What is the role of a counter in digital electronics?
o Correct Answer: c) To count the number of pulses
o Explanation: A counter counts the number of pulses or events, often used in timing
and sequencing.
16. In digital systems, what is the function of an adder circuit?
o Correct Answer: a) Performs arithmetic addition
o Explanation: An adder circuit performs arithmetic addition of binary numbers.
17. What is the purpose of a register in digital electronics?
o Correct Answer: a) Stores binary data temporarily
o Explanation: Registers are used to temporarily store binary data within a digital
system.
18. Which logic gate outputs true if and only if all its inputs are true?
o Correct Answer: a) AND
o Explanation: The AND gate outputs true only when all of its inputs are true.
19. What is the primary function of a shift register?
o Correct Answer: b) Stores data and shifts it sequentially
o Explanation: A shift register stores data and shifts it through its stages
sequentially.
20. What is the purpose of a comparator in digital systems?
o Correct Answer: b) Compares two binary numbers
o Explanation: A comparator compares two binary numbers and determines their
relative sizes.
21. In digital electronics, what does the term "clock cycle" refer to?
o Correct Answer: d) The interval between two successive clock pulses
o Explanation: A clock cycle is the time interval between successive pulses of the
clock signal.
22. What does ALU stand for in digital computers?
o Correct Answer: b) Arithmetic and Logic Unit
o Explanation: The ALU performs arithmetic and logic operations in a computer.
23. Which component is responsible for storing instruction sets in a digital computer?
o Correct Answer: b) ROM
o Explanation: ROM (Read-Only Memory) stores firmware or instruction sets in a
computer.
24. What is the primary role of a multiplexer (MUX) in digital systems?
o Correct Answer: b) To select one of many inputs and pass it to the output
o Explanation: A multiplexer (MUX) selects one of several input signals and
forwards it to the output.
25. What is the function of a demultiplexer in digital electronics?
o Correct Answer: c) Divides one signal into multiple outputs
o Explanation: A demultiplexer takes a single input signal and routes it to one of
several output lines.
26. Which logic gate has an output that is true if and only if both inputs are false?
o Correct Answer: d) NOR
o Explanation: The NOR gate outputs true only when both of its inputs are false.
27. What is the purpose of a flip-flop in digital circuits?
o Correct Answer: b) To store one bit of binary data
o Explanation: A flip-flop stores a single bit of binary data.
28. In digital systems, what does the term "bus" refer to?
o Correct Answer: a) A group of wires carrying related signals
o Explanation: A bus is a set of wires used to transmit related signals between
different parts of a digital system.
29. What is the role of an encoder in digital electronics?
o Correct Answer: b) Converts binary data into a specific code
o Explanation: An encoder converts binary data into a specific code or format.
30. Which logic gate outputs true if and only if one input is true and the other is false?
o Correct Answer: d) XOR
o Explanation: The XOR (exclusive OR) gate outputs true when exactly one of its
inputs is true.
31. What is the primary function of a counter in digital systems?
o Correct Answer: c) To count the number of pulses
o Explanation: A counter counts the number of pulses or events.
32. What is the purpose of a multiplexer (MUX) in digital circuits?
o Correct Answer: b) To combine multiple signals into one
o Explanation: A multiplexer (MUX) combines multiple input signals into a single
output.
33. Which type of logic gate outputs true if and only if at least one of its inputs is false?
o Correct Answer: c) NAND
o Explanation: The NAND gate outputs true if at least one of its inputs is false.
34. What does CMOS stand for in digital electronics?
o Correct Answer: a) Complementary Metal Oxide Semiconductor
o Explanation: CMOS stands for Complementary Metal Oxide Semiconductor, a
technology for integrated circuits.
35. In digital electronics, what is a flip-flop?
o Correct Answer: c) A circuit element that stores state information
o Explanation: A flip-flop is a circuit element used to store state information,
typically one bit.
36. Which logic gate has an output that is true only if both of its inputs are true?
o Correct Answer: a) AND
o Explanation: The AND gate outputs true only when both of its inputs are true.
37. What is the binary equivalent of the decimal number 47?
o Correct Answer: b) 101111
o Explanation: The decimal number 47 converts to binary 101111. In binary, 47 is
represented as 32+16+8+2+1=10111132 + 16 + 8 + 2 + 1 =
10111132+16+8+2+1=101111.
38. Which logic gate is represented by the Boolean expression A‾⋅B\overline{A} \cdot
BA⋅B?
o Correct Answer: a) AND
o Explanation: The Boolean expression A‾⋅B\overline{A} \cdot BA⋅B represents
the AND gate operation combined with NOT on A.
39. What is the octal equivalent of the binary number 110010?
o Correct Answer: a) 62
o Explanation: Binary 110010 converts to octal 62. Group the binary digits in sets
of three from the right (110 010), where 110 is 6 and 010 is 2 in octal.
40. What is the primary purpose of a decoder in digital electronics?
o Correct Answer: d) Converts binary data to a specific set of outputs
o Explanation: A decoder converts binary data into a specific output pattern.
