Sign In

Computer Science for IGCSE & O level - Boolean Logic (Section 7)

1
What type of gate is created by inverting the output of a NOR gate?
Answer
(B)
OR gate
2
The Boolean expression for an OR gate with inputs A and B is:
Answer
(B)
A + B
3
If, in a half adder, A=1 and B=1, what are the values of Sum and Carry?
Answer
(B)
Sum = 0, Carry = 1
4
In a logic circuit, the symbol '¬' or an overbar on a variable represents which operation?
Answer
(C)
NOT
5
In digital logic, the output of a gate is usually represented as:
Answer
(C)
Binary values
6
What is the result of the Boolean expression A + 0?
Answer
(C)
A
7
What type of gate is created by inverting the output of an OR gate?
Answer
(C)
NOR
8
How many inputs are required to generate a full adder circuit?
Answer
(C)
3
9
Which logic gate outputs a 1 if any of the inputs is 1?
Answer
(B)
OR
10
What is the output of a NAND gate if the inputs are 1 and 0?
Answer
(B)
1
11
What logic operation is represented by the symbol ‘+’ in Boolean algebra?
Answer
(B)
OR
12
What is the output of an XOR gate if the inputs are 0 and 1?
Answer
(B)
1
13
Which logical operations does an AND gate perform?
Answer
(B)
Outputs 1 only if all inputs are 1; otherwise 0.
14
Which gate's output is HIGH (1) if *any* of its inputs are HIGH?
Answer
(B)
OR
15
Which of these gates is considered to be the complement of an OR gate?
Answer
(C)
NOR
16
What logic gate combines the functions of AND and NOT?
Answer
(B)
NAND gate
17
If A = 1 and B = 1, what is the output of a NAND gate?
Answer
(A)
0
18
What does the term 'truth table' represent in digital electronics?
Answer
(B)
A table showing the output of a gate for all input combinations
19
What is the result of the Boolean expression A . A'?
Answer
(A)
0
20
What type of gate produces an output HIGH (1) only if the inputs are different?
Answer
(C)
XOR
21
If the inputs to an AND gate are A=1 and B=1, what is the output?
Answer
(B)
1
22
What is the fundamental operation of a NOT gate?
Answer
(B)
Inversion
23
A logic gate with two inputs produces a HIGH (1) output only when both inputs are LOW (0). What type of gate is it?
Answer
(C)
NOR
24
Which of the following is the symbol for the AND gate?
Answer
(B)
·
25
What is the function performed by a NOT gate?
Answer
(B)
Inverts the input signal
26
Which of the following are the correct ways to describe the function of a logic gate?
Answer
A
B
C
27
Which of the following correctly describes the output of a 2-input XOR gate?
Answer
(C)
Output is 1 if the inputs are different
28
What is the definition of a 'logic circuit'?
Answer
(B)
A circuit that uses logic gates to perform operations on binary inputs.
29
What does the term 'half adder' refer to?
Answer
(A)
A logic circuit that adds two single binary digits.
30
What is the output of an XOR gate if the inputs are 1 and 1?
Answer
(A)
0
31
What is the main function of the half adder circuit?
Answer
(C)
Adding two binary numbers
32
What output is produced by a NOR gate if both inputs are 1?
Answer
(A)
0
33
Which one is a fundamental part of a digital computer?
Answer
(A)
Logic gates
34
If an input signal to a NOT gate is HIGH, what is the output signal?
Answer
(B)
LOW
35
In Boolean algebra, what does the complement of a variable represent?
Answer
(B)
The inverse or NOT operation
36
What is the output of a 2-input NOR gate if A = 1 and B = 0?
Answer
(A)
0
37
In a digital circuit, a NOT gate will change the state of a signal. What describes the state of a signal?
Answer
(B)
The voltage level of the signal.
38
Which gate's output is HIGH if and only if all inputs are HIGH?
Answer
(A)
AND
39
What is the output of a NOT gate if the input is HIGH (logic 1)?
Answer
(B)
LOW (0)
40
Which gate outputs '1' if all inputs are '1'?
Answer
(A)
AND
41
Which of the following gates is considered a 'universal' gate?
Answer
(C)
NAND gate
42
Which gate's output is HIGH only when the inputs are different?
Answer
(C)
XOR
43
Which of the following is equivalent to a XOR gate using only AND, OR, and NOT gates?
Answer
(B)
(A AND NOT B) OR (NOT A AND B)
44
What is the function of the NOT gate?
Answer
(B)
To invert the input signal.
45
What does the term 'truth table' represent in digital logic?
Answer
(D)
A table showing all possible combinations of inputs and their corresponding outputs
46
In Boolean algebra, the OR operation is represented by which symbol?
Answer
(A)
+
47
The full adder circuit is often built from:
Answer
(A)
Two half adders and an OR gate
48
What is the output of an XNOR gate with inputs A=0 and B=1?
Answer
(A)
0
49
What is the output of a 3-input OR gate when all inputs are 0?
Answer
(A)
0
50
Which gate is used to change a 1 input to a 0 output?
Answer
(C)
NOT gate