Computer Science/IT MCQs
Topic Notes: Computer Science/IT
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
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
211
Emojis are represented using which character set?
Answer:
Unicode
Emojis are characters just like letters and numbers. They have their own specific code points within the Unicode standard.
212
A group of 8 bits is commonly known as a:
Answer:
Byte
A byte is a standard unit of digital information in computing and consists of 8 bits. It can represent 2^8 = 256 different values.
213
The easiest way to convert between hexadecimal and octal is to:
Answer:
Convert to binary first
Since both octal and hexadecimal have bases that are powers of 2, converting to binary is a straightforward intermediate step. Convert the source number to binary, then regroup the bits for the target base (groups of 3 for octal, groups of 4 for hexadecimal).
214
Which number system would be the most efficient for storing a number in terms of the number of digits required?
Answer:
Hexadecimal
Number systems with a higher base are more compact, meaning they require fewer digits to represent the same value. Of the options listed, hexadecimal has the highest base (16).
215
Which of the following digits is NOT a valid digit in the octal number system?
Answer:
8
Since the octal system is base-8, its digits only go from 0 to 7. The digit 8 does not exist in this system.
216
[cite_start]Which coding scheme uses 16-bit to represent a symbol? [cite: 470]
Answer:
Unicode
The foundational version of the Unicode standard uses 16 bits for each character. [cite: 471] [cite_start]This allows for a much larger character set than 8-bit schemes like ASCII and EBCDIC, making it possible to represent characters from nearly all modern languages. [cite: 472]
217
What is the hexadecimal equivalent of the decimal number 256?
Answer:
(100)₁₆
256 / 16 = 16 with a remainder of 0. Then, 16 / 16 = 1 with a remainder of 0. The result is 1. Reading from bottom to top gives (100)₁₆.
218
A logic circuit with two inputs has how many possible input combinations?
Answer:
4
For 'n' inputs, there are 2^n possible combinations. For 2 inputs, there are 2² = 4 combinations (00, 01, 10, 11).
219
[cite_start]How many bits are there in 8 bytes? [cite: 433]
Answer:
64 bits
A single byte is defined as a sequence of 8 bits. [cite: 434] [cite_start]To find the total number of bits in 8 bytes, you multiply the number of bytes by 8. So, 8 bytes × 8 bits/byte = 64 bits. [cite: 435]
220
The value of each position in a number system is determined by a power of its:
Answer:
Base
In any positional number system, the value of a digit is its face value multiplied by a power of the system's base, determined by its position. For example, in the decimal number 123, the '1' represents 1 \* 10^2.