Q41. In the binary number system, what does a single "bit" represent?
Computers, Information and Communication Technology: RAS Prelims MCQs
200 RAS Prelims MCQs on computers, information and communication technology cover the generations of computers, the parts of the CPU, memory types and networking. The first and second generations, analog computers, the control unit, cache and RAM, the memory hierarchy and the SSD are asked as definitions and sequences, with the explanations giving the reason for each design.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 41–50 of 200 questions
Q42. How many bits constitute a ‘nibble’ in data representation?
Explanation
A nibble is a data unit that consists of exactly 4 bits, representing half of a standard 8-bit byte. Because a nibble contains four binary digits, it can represent sixteen distinct values, ranging from 0 to 15. This unit is particularly useful in hexadecimal representation, as each hexadecimal digit corresponds directly to the value of a single nibble in binary.
Q43. Given below are two statements regarding character encoding.
Statement I: ASCII is an encoding standard used to represent text in computers.
Statement II: Unicode was developed because ASCII did not have enough capacity to represent characters of all world languages.
Which of the above statement(s) is/are correct?
Statement I: ASCII is an encoding standard used to represent text in computers.
Statement II: Unicode was developed because ASCII did not have enough capacity to represent characters of all world languages.
Which of the above statement(s) is/are correct?
Explanation
ASCII was the early standard for character encoding, but its limited capacity could only represent English characters and basic symbols. As computing became global, Unicode was developed to provide a unique number for every character across all world languages. Both standards are essential for text representation, with Unicode effectively expanding upon the foundation laid by ASCII to ensure universal compatibility.
Q44. Given below are two statements: one is labelled as Assertion (A) and the other is labelled as
Reason (R).
Assertion (A): The binary number system uses base 2.
Reason (R): Digital computer circuits are constructed using electronic switches that can only exist in two states: on or off.
Reason (R).
Assertion (A): The binary number system uses base 2.
Reason (R): Digital computer circuits are constructed using electronic switches that can only exist in two states: on or off.
Explanation
Digital computers utilize the binary number system because it perfectly aligns with the physical reality of electronic circuits. These circuits are built using transistors that function as switches, which are either conducting electricity or not. By using base 2, computers can reliably represent data and perform logical operations using these two fundamental states, making the binary system the most efficient architecture.
Q45. Why is the hexadecimal system frequently used in computer science alongside binary?
Explanation
Hexadecimal is used in computer science as a convenient way to represent long strings of binary digits. Since one hexadecimal digit represents exactly four bits, it significantly reduces the length of data strings, making them easier for humans to read and debug. This shorthand is commonly seen in memory addresses, color codes, and various low-level programming tasks where binary clarity.
Q46. Identify the incorrect statement regarding computer data storage units.
Explanation
Computer data storage units follow a hierarchical structure based on powers of two. While 8 bits form a byte and 1024 bytes form a kilobyte, the progression continues to megabytes, gigabytes, and terabytes. The assertion that one megabyte equals 1024 gigabytes is mathematically incorrect; in reality, it takes 1024 megabytes to constitute a single gigabyte, reflecting the increasing scale of storage.
Q47. What is the binary equivalent of the decimal number 13?
Explanation
Converting the decimal number 13 to binary involves dividing by two and tracking the remainders. Dividing 13 by 2 gives a remainder of 1, 6 by 2 gives 0, 3 by 2 gives 1, and 1 by 2 gives 1.
Q48. Match List I with List II.
| Unit | Value in Bytes |
|---|---|
| A. Kilobyte | i. 220 bytes |
| B. Megabyte | ii. 210 bytes |
| C. Gigabyte | iii. 240 bytes |
| D. Terabyte | iv. 230 bytes |
Explanation
Data storage units are based on binary multipliers where each level increases by a factor of 2 to the power of 10. A kilobyte is 2 to the 10th power, a megabyte is 2 to the 20th power, a gigabyte is 2 to the 30th power, and a terabyte is 2 to the 40th power. This exponential scale allows for precise measurement.
Q49. Identify the odd one out among the numerical systems used in computing.
Explanation
Binary, octal, and hexadecimal are all positional numeral systems used in computing to represent data and memory addresses. Each has a specific base--2, 8, and 16, respectively--that facilitates efficient machine processing and human interpretation. "Algorithmic" refers to a set of step-by-step instructions for solving problems rather than a numerical system, making it the distinct outlier in this categorization.
Q50. Which pair represents correct character encoding schemes used in computing?
Explanation
Character encoding schemes are essential for translating human-readable text into digital format. ASCII is the most widely recognized standard for English characters, while EBCDIC is an older encoding scheme primarily used on IBM mainframe systems. These standards ensure that text is stored and transmitted consistently across different hardware platforms, unlike networking protocols or file systems which serve entirely different technical purposes.Answer key for these questions
| Q | Correct answer |
|---|---|
| 41 | (c) A discrete value of either 0 or 1 |
| 42 | (b) 4 bits |
| 43 | (a) Both Statement I and II are correct |
| 44 | (a) Both A and R are true and R is the correct explanation of A. |
| 45 | (c) Human-friendly shorthand for binary |
| 46 | (d) One Megabyte (MB) equals 1024 Gigabytes (GB). |
| 47 | (a) 1101 |
| 48 | (a) A-ii, B-i, C-iv, D-iii |
| 49 | (b) Algorithmic |
| 50 | (a) ASCII and EBCDIC |
Key facts from Computers, Information and Communication Technology
- First-generation computers used vacuum tubes; the second generation moved to transistors.
- Analog computers work on continuous variable data rather than discrete binary data.
- The Control Unit directs and coordinates the operations of the CPU.
- Cache memory gives the fastest access to the CPU; the hierarchy from fastest to slowest is registers, cache, RAM and magnetic disk.
- Adding more RAM to a system with many page faults reduces its dependence on virtual memory.
- An SSD differs from an HDD by the use of NAND flash memory.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Computers, Information and Communication Technology?
This page has 200 practice MCQs on Computers, Information and Communication Technology (Science and Technology). Each has the correct answer, and most have an explanation.
What was used in first-generation computers?
Vacuum tubes. They were large, used much power and produced heat. The second generation replaced them with transistors, which were smaller, faster and more reliable, and later generations moved to integrated circuits and microprocessors.
Which memory is fastest for the CPU?
Cache memory, apart from the registers inside the CPU. The memory hierarchy from fastest to slowest is registers, cache, RAM and magnetic disk, and capacity increases as speed falls.
How does an SSD differ from an HDD?
An SSD stores data in NAND flash memory with no moving parts, while a hard disk drive uses spinning magnetic platters. As a result an SSD is faster, quieter and more resistant to shock.