Computer Science for IGCSE & O level - Boolean Logic (Section 5)
1
If A = 1, B = 0, and C = 1. What would be the output for the expression: Y = (A AND B) OR C ?
Answer
(B)
1
2
What is the result of (1 + 0) in Boolean algebra?
Answer
(B)
1
3
Which of the following logic expressions is represented by the given logic circuit (refer to the images)?
Answer
(B)
(NOT A AND B) OR (NOT C OR (A AND B))
4
The XNOR gate can be thought of as a combination of which two basic gates?
Answer
(C)
XOR and NOT
5
Which of the following is a universal gate?
Answer
(C)
NAND gate
6
What is the output of a NOR gate if both inputs are 0?
Answer
(B)
1
7
Which of the following are the inputs of the NAND gate?
Answer
(A)
A and B
8
What is the main objective in using a logic expression?
Answer
(B)
To create an alternative method for representing a logic circuit and verify its correctness.
9
In a half-adder circuit, what are the two outputs?
Answer
(C)
Sum and Carry
10
What is the result of the logic operation 1 OR 1?
Answer
(B)
1
11
Which logic gate(s) can produce an output of 0 given inputs of 1 and 1?
Answer
A
C
D
12
If the inputs to a NAND gate are A=1 and B=0, what will be the output?
Answer
(B)
1
13
Which of these Boolean expression represents the XOR operation?
Answer
(C)
A XOR B
14
If A = 1 and B = 0, then what will be the output of a NAND gate?
Answer
(B)
1
15
Which of the following is NOT a fundamental logic gate?
Answer
(D)
XNOR
16
Which of the following operations represents the logical *AND*?
Answer
(B)
A . B
17
What is the output of a two-input NAND gate when the inputs are 1 and 0, respectively?
Answer
(B)
1
18
Which gate has the following truth table: A B | Output: 0 0 | 1, 0 1 | 0, 1 0 | 0, 1 1 | 0?
Answer
(D)
NOR
19
Which of the following correctly describes the behavior of an OR gate?
Answer
(B)
The output is high (1) if at least one of the inputs is high.
20
Which logic gate outputs a high signal (1) if and only if its inputs are different (one is 0 and the other is 1)?
Answer
(B)
XOR gate
21
What does the 'Karnaugh map' help with in Boolean algebra?
Answer
(A)
Simplifying logical expressions
22
What is the complement of a variable A in boolean algebra denoted by?
Answer
(B)
A'
23
What are the main components of a Full-adder?
Answer
(A)
Two half-adders and an OR gate.
24
Based on the examples, what is the most common format used to represent logic operations and circuit functions?
Answer
(D)
Truth tables
25
In a logic circuit, if the output is high (1) when any of the input conditions A, B, or C are present, which type of logic gate is used to achieve this?
Answer
(B)
OR gate
26
Which gate acts as an inverter?
Answer
(C)
NOT gate
27
Which logic gate requires all its inputs to be HIGH for a HIGH output?
Answer
(B)
AND
28
If the output of a logic gate is 1 only when both inputs are 1, what type of gate is it?
Answer
(B)
AND gate
29
What is the role of a 'circuit diagram'?
Answer
(C)
To graphically depict the arrangement of logic gates and their connections.
30
Which of the following statements correctly describes the behavior of a NAND gate?
Answer
(C)
The output is 0 only when all inputs are 1
31
What is the primary function of a logic gate?
Answer
(C)
To implement Boolean algebra functions.
32
What is the simplest logic gate that performs the function of summing two binary digits and producing a sum and a carry?
Answer
(B)
Half Adder
33
Which logic gate is considered an 'inverter'?
Answer
(C)
NOT
34
What is typically the first step in designing a logic circuit, as presented in the examples?
Answer
(C)
Create a truth table.
35
Which gate would be suitable for a circuit to check if two bits are equal?
Answer
(C)
XNOR
36
What is the simplified expression for the logic circuit A.0?
Answer
(B)
0
37
In the examples, what is the key function of the 'NOT' gate?
Answer
(B)
To invert the input signal.
38
In the examples, a logic expression is used to ____ the functionality of a logic circuit.
Answer
(B)
mathematically represent
39
What is the primary function of a logic circuit?
Answer
(C)
To make decisions based on input conditions.
40
What is the purpose of a truth table?
Answer
A
B
41
In a digital circuit, what does a high voltage typically represent?
Answer
(B)
1
42
Which of the following represents De Morgan's law?
Answer
B
C
43
If input A=1 and input B=0, what will be the output of a NOR gate?
Answer
(A)
0
44
In the context of the engine management system example, the output signal Y will be high when the motor speed is greater than 3000 rpm and the bearing temperature is <= 80C, or when the water velocity is > 4m/s. What type of gate is this essentially combining?
Answer
(A)
An OR gate and an AND gate.
45
What is the function of a full adder?
Answer
(B)
Add two binary digits including a carry-in
46
In a logic circuit, what does the term 'parameter' usually refer to?
Answer
(B)
An input condition being monitored.
47
How is the final logic circuit constructed, as demonstrated in the examples?
Answer
(B)
By combining intermediate logic circuits using AND and OR gates.
48
Which logic gate's output is HIGH (1) when either or both of its inputs are HIGH (1)?
Answer
(B)
OR gate
49
Which gate is known as the NOT OR gate?
Answer
(C)
NOR gate
50
Which gate's output is '1' only when all inputs are '0'?
