Computer Science for IGCSE & O level - Boolean Logic (Section 11)
1
In the context of binary addition, what does the 'carry' bit represent?
Відповідь
(B)
The amount to be carried over to the next most significant bit column.
2
If you have an OR gate, and you want the output to be 0, what must the inputs be?
Відповідь
(C)
Both 0
3
Which gate is the inverse of an OR gate?
Відповідь
(B)
NOR
4
In a digital circuit, a NAND gate can be formed by combining an AND gate and a:
Відповідь
(A)
NOT gate
5
In the half adder circuit, the output is a carry if both inputs are:
Відповідь
(B)
1
6
Which of the following is true about logic gates?
Відповідь
(B)
They are made up of thousands of transistors
7
Which of these is not a common logic gate?
Відповідь
(D)
NOR
8
What logic gate produces an output of 1 only if its inputs are different?
Відповідь
(C)
XOR
9
Which of the following logic gates produces a 1 output if and only if all its inputs are 0?
Відповідь
(C)
NOR
10
When both inputs to a NAND gate are HIGH, the output is:
Відповідь
(B)
LOW
11
What is the simplified form of the expression A OR (A AND B)?
Відповідь
(A)
A
12
Which logic gate produces an output that is the inverse of the OR gate's output?
Відповідь
(B)
NOR gate
13
What is the fundamental function of a logic gate in digital circuits?
Відповідь
(B)
To perform logical operations.
14
The NAND gate is equivalent to an AND gate followed by what logic gate?
Відповідь
(C)
NOT gate
15
Which of the following statements describes an XOR gate?
Відповідь
(C)
Outputs HIGH if and only if inputs are different
16
A NOR gate can be made using which combination of gates?
Відповідь
(B)
OR and NOT
17
Which is the equivalent expression for NOT (A AND B)?
Відповідь
(B)
NOT A OR NOT B
18
What does the term 'binary value' represent?
Відповідь
(B)
A number in base 2
19
What is the carry output in a half adder if A=1 and B=0?
Відповідь
(A)
0
20
In a half adder circuit, what does 'sum' represent?
Відповідь
(A)
The result of adding two input bits without considering the carry.
21
The output of a NAND gate is LOW only when:
Відповідь
(C)
All inputs are HIGH
22
What is the output of a NAND gate if both inputs are 1?
Відповідь
(A)
0
23
What is the output of an XNOR gate when the inputs are 1 and 1?
Відповідь
(B)
1
24
What is the result of the Boolean expression A + A?
Відповідь
(C)
A
25
What does a Karnaugh map (K-map) help to simplify?
Відповідь
(A)
Logic circuits
26
Which logic gate is the complement of an OR gate?
Відповідь
(B)
NOR
27
A logic gate's function can be completely described by:
Відповідь
(B)
A truth table
28
In a series of logic operations represented by a truth table, what defines an input?
Відповідь
(A)
Independent variables that affect output.
29
If A = 1, what is the result of NOT A?
Відповідь
(A)
0
30
If the inputs to a 2-input AND gate are A=0 and B=0, what is the output?
Відповідь
(A)
0
31
Which of the following is equivalent to the logic expression NOT(A AND B)?
Відповідь
(C)
NOT A OR NOT B
32
What does the 'sum' output represent in a half adder?
Відповідь
(B)
The result of the binary addition
33
What type of gate results from inverting the output of a NAND gate?
Відповідь
(B)
OR
34
What is the output of a 2-input XOR gate if the inputs are A=1 and B=0?
Відповідь
(B)
1
35
How many logic gates are used to build a half adder circuit?
Відповідь
(C)
3
36
Which of the following is the simplified Boolean expression for a NAND gate with inputs A and B?
Відповідь
(C)
(A . B)'
37
What is the output of a 2-input AND gate when A=1 and B=0?
Відповідь
(A)
0
38
Which logic gate has an output of 1 only when both inputs are 1?
Відповідь
(B)
AND gate
39
If the inputs of an AND gate are A = 1 and B = 0, what will be the output?
Відповідь
(A)
0
40
Which type of gate can be described as an 'inverter'?
Відповідь
(C)
NOT gate
41
What type of logic gate is described by the expression NOT(A OR B)?
Відповідь
(C)
NOR gate
42
Which of the following Boolean expressions is equivalent to a NAND gate?
Відповідь
(D)
(A * B)'
43
Which gate outputs a HIGH (1) unless both inputs are HIGH (1)?
Відповідь
(A)
NAND
44
Which of the following gates is the most suitable for the application of a 'voting' system, where the output should be HIGH if a majority of inputs are HIGH?
Відповідь
(B)
OR
45
What is the purpose of a decoder in digital circuits?
Відповідь
(C)
To select one of several output lines based on the input.
46
Which one is a key advantage of using logic gates in computers?
Відповідь
(C)
They are very reliable.
47
What is the purpose of the NOT gate in digital circuits?
Відповідь
(B)
To invert the signal.
48
How many input combinations exist for a logic gate with two inputs?
Відповідь
(C)
4
49
A truth table is a table that shows the output of a logic gate for every possible combination of:
Відповідь
(B)
Inputs and outputs.
50
Which of these is the correct expression for the NOT gate?
