Chapter 12. Software Development

Question 1

What is Boolean algebra?

Answer 1

• A branch of algebra that deals with true/false values.
• Uses logical operators like AND, OR, NOT to manipulate Boolean values.

Question 2

What are the basic logical operators in Boolean algebra?

Answer 2

• AND: Returns true if both operands are true.
• OR: Returns true if at least one operand is true.
• NOT: Inverts the truth value of the operand.

Question 3

What is a truth table?

Answer 3

• A table used to show all possible input values and their corresponding output values for a logic gate or Boolean expression.

Question 4

What is the function of an AND gate?

Answer 4

• Outputs true only if both inputs are true.
• Represented by the symbol ‘.’ or multiplication in Boolean expressions.

Question 5

What is the function of an OR gate?

Answer 5

• Outputs true if at least one input is true.
• Represented by the symbol ‘+’ or addition in Boolean expressions.

Question 6

What is the function of a NOT gate?

Answer 6

• Outputs the inverse of the input value.
• Represented by the symbol ‘¬’ or a bar over the input in Boolean expressions.

Question 7

What is a NAND gate?

Answer 7

• A combination of an AND gate followed by a NOT gate.
• Outputs true unless both inputs are true.

Question 8

What is a NOR gate?

Answer 8

• A combination of an OR gate followed by a NOT gate.
• Outputs true only if both inputs are false.

Question 9

What is an XOR gate?

Answer 9

• Outputs true if the inputs are different.
• Known as exclusive OR gate.

Question 10

What is an XNOR gate?

Answer 10

• Outputs true if the inputs are the same.
• Known as exclusive NOR gate.

Question 11

What are De Morgan’s laws in Boolean algebra?

Answer 11

• Two transformation rules that simplify the negation of conjunctions and disjunctions.
• ¬(A AND B) = ¬A OR ¬B, ¬(A OR B) = ¬A AND ¬B.

Question 12

What is the importance of Boolean algebra in computing?

Answer 12

• Fundamental in designing and simplifying digital circuits.
• Used in creating and optimizing logic gates and circuits.

Question 13

What is a logic circuit?

Answer 13

• A physical implementation of Boolean functions using logic gates.
• Used to perform computations in digital devices.

Question 14

What is the difference between combinational and sequential logic circuits?

Answer 14

• Combinational logic circuits: Output depends only on current inputs.
• Sequential logic circuits: Output depends on current inputs and previous states.

Question 15

What is a flip-flop in digital electronics?

Answer 15

• A basic memory element in sequential logic circuits.
• Stores a single bit of data, used in registers and memory units.

Question 16

What is a half adder?

Answer 16

• A digital circuit that adds two binary digits and produces a sum and a carry output.
• Uses XOR and AND gates.

Question 17

What is a full adder?

Answer 17

• A digital circuit that adds three binary digits (including carry from previous addition) and produces a sum and carry output.
• Can be built using two half adders and an OR gate.

Question 18

What is a multiplexer?

Answer 18

• A device that selects one of several input signals and forwards the selected input to a single output line.
• Used to increase the efficiency of data handling.

Question 19

What is a demultiplexer?

Answer 19

• A device that takes a single input signal and distributes it to one of several output lines.
• Used to send data from one source to multiple destinations.

Question 20

What is a binary decoder?

Answer 20

• A device that converts binary input data into a specific output.
• Used in memory address decoding and other applications.

Question 21

What is a binary encoder?

Answer 21

• A device that converts a specific input into binary code.
• Used to reduce the number of input lines needed.

Question 22

What are the advantages of using Karnaugh maps (K-maps)?

Answer 22

• Simplifies Boolean expressions to minimize the number of logic gates.
• Provides a visual method to simplify complex Boolean functions.

Question 23

What is the difference between a latch and a flip-flop?

Answer 23

• Latch: A simple memory device that operates with a level-triggered input.
• Flip-flop: A more complex memory device that operates with an edge-triggered input.

Question 24

What is the purpose of using a shift register?

Answer 24

• A sequential logic circuit used for storing and shifting data.
• Moves data in a specific direction (left or right) with each clock pulse.

Question 25

What are the typical applications of Boolean algebra in computer science?

Answer 25

• Design of digital circuits and logic gates.
• Development of algorithms for data processing and decision-making.