Computer Science - IT MCQs
Topic Notes: Computer Science - IT
<p>MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.</p>
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
1
What does the radix (base) of a number system represent?
Answer:
Equals the number of its distinct counting digits
The radix, or base, of a positional numeral system is the number of unique digits, including zero, used to represent numbers in that system.
2
Which of the following statements accurately describes the 2-out-of-5 code?
Answer:
it is unweighted code
The 2-out-of-5 code is a type of error-detecting code used in digital systems. It is classified as an unweighted code because the position of the bits does not correspond to a specific numerical weight, unlike binary-coded decimal (BCD) systems.
3
Under what specific condition will the output of a two-input OR gate be equal to 0?
Answer:
both inputs are 0
An OR gate is a fundamental digital logic gate that implements logical disjunction. According to its truth table, the output of an OR gate is high (1) if at least one of its inputs is high.
4
What is the binary representation of the hexadecimal number 3D?
Answer:
1111012
To convert hexadecimal 3D to binary, convert each digit individually. Hexadecimal 3 is 0011 in binary, and D (which represents decimal 13) is 1101 in binary. Combining these results in 00111101.
5
Which number system is utilized by modern computers to internally represent characters and numerical values?
Answer:
Binary
Modern digital computers operate using the binary number system, which consists of only two digits: 0 and 1. These represent the 'off' and 'on' states of electronic switches (transistors) within the CPU.
6
Which number system do modern computers use to internally represent characters and numerical data?
Answer:
Binary
Modern computers operate using the binary number system, which consists of only two digits: 0 and 1. This system is ideal for digital electronics because it corresponds directly to the 'on' and 'off' states of transistors.
7
Which class of computer systems typically utilizes the 8-bit EBCDIC character encoding scheme?
Answer:
Mainframe computers
EBCDIC, which stands for Extended Binary Coded Decimal Interchange Code, is an 8-bit character encoding system developed by IBM. It was primarily designed for use on IBM mainframe and midrange computer systems.
8
If a computer system uses 16 bits to specify addresses in RAM, how many unique addresses can be accessed?
Answer:
Any of the above
With 16 bits, the total number of unique addresses is 2 raised to the power of 16, which equals 65,536. This value is also commonly referred to as 64K (where 1K = 1024).
9
Which logic gate produces a high output only when none of its input terminals receive a pulse?
Answer:
NOR
A NOR gate is a digital logic gate that implements logical NOR. It produces a high output (1) only if all of its inputs are low (0). If any input is high, the output becomes low.
10
Which of the following values is not a valid binary number?
Answer:
202
The binary number system uses only two digits: 0 and 1. Therefore, any number containing digits other than 0 or 1, such as 2, is not a valid binary number.