Computer Science | Mock Test-II | Entrance Exam | MCQs |

A hard disk drive (HDD) is a type of storage device that can be carried around, especially if it is designed to be portable. There are several reasons why this is the correct answer:

Portability: Portable hard disk drives are designed to be compact and lightweight, making them easy to carry around. They often come with a durable casing to protect them from physical damage.

Storage Capacity: Portable hard disk drives can offer a large amount of storage, typically ranging from hundreds of gigabytes (GB) to several terabytes (TB). This makes them suitable for storing large amounts of data, such as documents, photos, videos, and software.

Connectivity: They usually connect to computers and other devices via USB, making them easy to use with multiple devices.

Durability: Modern portable hard disk drives are built to withstand the rigors of travel, including potential drops and impacts.

Let's see from the oprion

b. System cabinet: A system cabinet (or computer case) houses all the internal components of a desktop computer. It is typically large, heavy, and not designed for portability.

c. Hard disk: While technically correct that a hard disk is a storage device, the term "hard disk" usually refers to the internal disk inside a computer, which is not designed to be portable. You would have to remove it from the computer and place it in a suitable enclosure to carry it around safely.

d. Floppy disk: Floppy disks are indeed portable storage devices, but they are largely obsolete due to their extremely limited storage capacity (typically 1.44 MB) and the lack of modern devices with floppy disk drives. They are not practical for today's storage needs.

Hence, the correct answer is option a. Hard disk drive (HDD)

Here's an explanation for why digital computers are superior to analog computers in terms of cost, speed, and accuracy:

1. Cost:
   • Digital Computers: Over time, the cost of digital computers has decreased significantly due to advancements in technology and mass production. Digital components like microprocessors, memory chips, and other integrated circuits are produced at scale, making them relatively inexpensive.
   • Analog Computers: Analog computers are generally more expensive to build and maintain. They require precise components that often need to be custom-made, which can drive up costs
2. Speed:
   • Digital Computers: Digital computers can process data at extremely high speeds, thanks to high-frequency clock rates and advanced processing techniques. They can perform millions or even billions of calculations per second.
   • Analog Computers: Analog computers are typically slower because they rely on physical processes (such as electrical or mechanical systems) to simulate problems. These processes do not operate as quickly as the electronic processes in digital computers.
3. Accuracy:
   • Digital Computers: Digital computers provide high accuracy and precision in calculations. They represent data using discrete binary values (0s and 1s), which minimizes errors. The precision of digital computers is only limited by the number of bits used in their calculations.
   • Analog Computers: Analog computers are less accurate because they rely on continuous physical quantities to represent data. These continuous signals can be subject to noise and degradation, leading to less precise results. The accuracy of analog computers is often limited by the quality of the components and the conditions under which they operate.

Let' see from the option

b. cost, accuracy and versatility: While digital computers are versatile and can handle a wide range of applications, the main distinguishing factors are cost, speed, and accuracy.

c. cost, speed and space requirements: While digital computers can be more compact and space-efficient, space requirements are not as critical a factor as speed and accuracy when comparing digital and analog computers.

d. all of these: This is not correct because versatility and space requirements are not as defining as cost, speed, and accuracy.

Hence, the correct answer is option a. cost, speed and accuracy

Here's an explanation for why DOS is not an example of application software:

Application Software:

Application software is designed to help users perform specific tasks. Examples include word processors, spreadsheets, graphics software, and database management systems. These are programs that run on top of the operating system to provide specific functionalities to the user.

Examples:

a. Computer graphics: This refers to software used for creating and manipulating visual content, such as Adobe Photoshop or CorelDRAW. This is application software because it helps users create and edit images.

c. Spreadsheet: This refers to software like Microsoft Excel or Google Sheets, used for organizing, analyzing, and storing data in tabular form. This is also application software.

d. Word Processing: This refers to software like Microsoft Word or Google Docs, used for creating, editing, and formatting text documents. This is application software as well.

DOS (Disk Operating System):

DOS is an example of system software, not application software. It is an operating system that provides a platform for application software to run. DOS manages hardware resources and provides essential services to applications, but it does not perform specific tasks for the user like application software does.

Hence, the correct answer is option b. DOS

OMR (Optical Mark Recognition):

OMR technology is used to detect marks made on paper, such as filled-in bubbles or checkboxes. This is commonly used in multiple-choice examination sheets where students mark their answers.

OMR scanners can quickly read and process large volumes of answer sheets, making it efficient for scoring exams and assessments.

The accuracy and speed of OMR technology make it ideal for academic testing, where timely and accurate results are essential.

Let's see from the option

b. OCR (Optical Character Recognition): OCR is used to convert different types of documents, such as scanned paper documents or images, into editable and searchable data. While OCR is valuable for digitizing printed text, it is not typically used for academic testing.

c. MICR (Magnetic Ink Character Recognition): MICR is used primarily in the banking industry to read information printed with magnetic ink, such as checks. It is not relevant to academic testing.

d. POS (Point of Sale): POS systems are used in retail environments to process sales transactions. They are not related to academic testing.

Hence, the correct answer is option a. OMR

Memory:

Memory is crucial for storing data and instructions that the computer needs to perform tasks. It includes both volatile memory (RAM) and non-volatile memory (hard drives, SSDs). Without sufficient memory, a computer cannot run programs efficiently or store necessary information.

Accuracy:

Computers are designed to perform calculations and process data with a high degree of accuracy. This precision is essential for tasks ranging from basic arithmetic to complex scientific computations. Errors in computing can lead to significant problems, so accuracy is a fundamental strength.

Speed:

One of the most notable strengths of computers is their speed. They can perform millions or even billions of instructions per second, allowing them to process large amounts of data quickly and efficiently. This speed is what makes computers so powerful and versatile.

Hence, the correct answer is option d. All of these

Definition of a Bit:

A bit is the most basic unit of data in computing and digital communications. It stands for "binary digit."

Binary System:

The binary system is a base-2 numeral system that uses only two digits: 0 and 1. Each bit in a binary number represents a power of 2, similar to how each digit in a decimal number represents a power of 10.

Usage:

Bits are the building blocks of digital data. Multiple bits can be combined to represent more complex information. For example, a byte consists of 8 bits and can represent 256 different values (from 0 to 255 in decimal).

Let's see from the option

a. Hexadecimal digit: The hexadecimal system is a base-16 numeral system that uses sixteen distinct symbols: 0-9 and A-F. A hexadecimal digit is not represented by a single bit but rather by 4 bits (since 24^=16).

b. Octal digit: The octal system is a base-8 numeral system that uses eight distinct symbols: 0-7. An octal digit is represented by 3 bits (since 2^3=8).

c. Decimal digit: The decimal system is a base-10 numeral system that uses ten distinct symbols: 0-9. A decimal digit is not directly represented by bits in the same straightforward way as binary digits.

Hence, the correct answer is option d. Binary digit

Binary System in Computing:

In computing, memory and storage are often measured using binary prefixes. The binary system is based on powers of 2, which aligns with the binary nature of computer processing.

Definition of a Kilobyte:

A kilobyte (KB) is defined as 2^10 bytes. This is because 1024 (which is 2^10) is the closest power of 2 to 1000.

Therefore, 1 kilobyte (KB) = 1024 bytes.

Historical and Practical Usage:

Historically, the term "kilobyte" was used to represent 1024 bytes in the context of computer memory because it conveniently fits with the binary system.

However, in some contexts, such as hard drive storage, manufacturers might use the metric definition of kilobyte (1000 bytes) to simplify marketing. In technical contexts, especially related to computer memory, 1 KB is almost universally accepted to mean 1024 bytes.

Let's see from the option

a. 1000 bytes: This is the metric system definition of a kilobyte, but in computing, 1 KB is traditionally 1024 bytes.

c. 2048 bytes: This is not a standard definition for a kilobyte. 2048 bytes would be equal to 2 kilobytes (1024 bytes × 2).

d. 512 bytes: This is half of a kilobyte (1024 bytes), so it is not correct for defining a kilobyte.

Hence, the correct answer is option b. 1024 bytes

Data Processing:

Data processing involves the collection, manipulation, and transformation of raw data into a meaningful form. This can include operations such as sorting, calculating, categorizing, and summarizing.

Definition of Information:

Information is processed data that is organized, structured, or presented in a given context to make it meaningful and useful. It is the end result of data processing.

Examples:

For instance, raw sales data (numbers) can be processed to generate reports (information) that show trends, averages, and summaries which can be used for decision-making.

Let's see from the option

a. Software program: This is a set of instructions that tells the computer how to process data, but it is not the product of data processing.

b. Hard copy output: This refers to the physical printout of data or information, such as printed reports or documents. It is a medium for delivering information but not the product itself.

d. Data: This refers to raw facts and figures that need to be processed to become useful. Data is the input to the data processing system, not the product.

Hence, the correct answer is option c. Information

CPU (Central Processing Unit):

The CPU is the brain of the computer. It performs calculations and executes instructions that drive all other components. It processes data and controls the flow of information through the system.

Memory:

Memory refers to the computer's storage space where data and instructions are kept temporarily or permanently. This includes RAM (Random Access Memory) for temporary storage and faster access, and ROM (Read-Only Memory) for permanent storage of essential system instructions.

I/O (Input/Output):

I/O refers to the input and output systems of the computer. Input devices (like keyboards and mice) allow users to enter data into the computer, while output devices (like monitors and printers) present data to the user. The I/O subsystem handles the communication between the computer and external devices.

Let's see from the option

a. CPU, Memory, tape: While the CPU and Memory are fundamental components, "tape" is an older form of storage and not as commonly used as a primary component in modern systems.

c. Tape, I/O, Floppy disk: Tape and floppy disks are both storage mediums that have largely been replaced by more modern storage solutions. They are not considered fundamental components of a computer's architecture.

d. I/O, printer, mouse: This option focuses on peripherals (a printer and a mouse are external devices), which are important for user interaction but not fundamental components of the computer's core system.

Hence, the correct answer is option b. CPU, I/O, Memory

Passwords:

Passwords are a security measure used to authenticate and authorize users before granting access to a computer system or network. They are designed to verify that the user is who they claim to be.

Passwords typically consist of a combination of letters, numbers, and special characters, and are known only to the user and the system. They help protect sensitive data and prevent unauthorized access.

Let's see from the option

a. Binary pass: This term is not commonly used in computer security. Binary codes are used in many aspects of computing, but "binary pass" does not specifically refer to access control.

b. ASCII Codes: ASCII (American Standard Code for Information Interchange) codes are used to represent text in computers and other devices. They are not used for access control but for encoding characters.

d. Code words: While code words could theoretically be used in some security contexts, they are not a standard method for controlling access to computers. Passwords are the widely accepted and standard method for this purpose.

Hence, the correct answer is option c. Passwords