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
61
What is the result of (1000)₂ - (0001)₂?
Answer:
(0111)₂
(In decimal: 8 - 1 = 7). This requires borrowing across all the zero columns.
62
What is the value of a double word?
Answer:
32 bits
In computer architecture, the size of a "word" depends on the processor (often 16 bits in older systems). [cite: 438] [cite_start]A "double word" or "dword" is defined as being twice the size of a standard word. [cite: 439] In a 16-bit architecture, a double word is 32 bits (4 bytes).
63
ASCII is a binary code that represents text. What does ASCII stand for?
Answer:
American Standard Code for Information Interchange
ASCII is the most common character encoding standard for representing text in computers.
64
A text file containing "Hello World" would have the same file size if saved in ASCII or UTF-8. Why?
Answer:
"Hello World" contains only characters that are in the standard ASCII set
Since all the characters in "Hello World" (letters, space) are part of the original 128 ASCII characters, UTF-8 will use only a single byte for each one, resulting in the exact same binary representation and file size as an ASCII-encoded file.
65
Which logic gate is a combination of an AND gate followed by a NOT gate?
Answer:
NAND
The name "NAND" is a contraction of "NOT AND". Its output is the inverse of an AND gate.
66
The decimal number system uses how many unique digits?
Answer:
10
The decimal system, which we use in everyday life, is a base-10 system. It uses ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.
67
What happens if you subtract 32 from the ASCII decimal value of a lowercase letter?
Answer:
You get the ASCII value of the corresponding uppercase letter
There is a consistent difference of 32 between the decimal ASCII codes for lowercase and uppercase letters. For example, 'a' is 97 and 'A' is 65 (97 - 32 = 65).
68
What is a "code page"?
Answer:
A list of characters used in older, pre-Unicode encoding systems
Before Unicode, different "code pages" were used to support different languages. Each code page was a table of 256 characters, with the lower half being ASCII and the upper half varying by region (e.g., Code Page 437 for DOS, Code Page 1252 for Windows).
69
In the context of computing and digital information, what is the full form or origin of the term 'bit'?
Answer:
Binary digit
The term 'bit' is a portmanteau, which is a blend of parts of two (or more) words and their meaning into a single new word. Specifically, 'bit' is derived from 'binary digit'. It was coined by mathematician John Tukey in 1947. A bit is the most fundamental unit of data in computing and digital communications. It represents the smallest piece of information and can only have one of two states, typically represented as 0 or 1 (on/off, true/false, etc.). This binary nature is foundational to how computers process and store all types of data.
70
Which of the following does the abbreviation EBCDIC stand for?
Answer:
Extended Binary Coded Decimal Interchange Code
EBCDIC is an acronym for Extended Binary Coded Decimal Interchange Code. This character encoding system was developed by IBM and is primarily used on their mainframe and midrange computer systems. Unlike ASCII, which is more commonly used in general computing, EBCDIC is an 8-bit encoding, meaning it can represent 256 different characters. It defines how letters, numbers, and symbols are represented in binary form within these specific computing environments.