Computer System Organization

A program which acts as an interface between the user and hardware is called Operating System.

A collection of 4 bits is called a Nibble.

Binary number system has digits as 0 and 1.

A collection of 8 bits is called a Byte.

Joystick is a pointing device used for playing games on a computer.

ROM is read-only memory that stores some pre-written instructions.

The ALU in computers is capable of performing arithmetic and logical operations.

Control unit controls all the hardware operations of a computer system.

A Hard Disk is a non-volatile high-capacity storage device ranging from 1 GB to several terabytes.

Cache memory speeds up access to data and instructions stored in RAM.

Process is the term used for a program being run by the computer.

Control unit sends control signals to ALU and memory for carrying out the required operations.

Answer

True

Reason — The Control unit controls flow of data from input devices to memory and from memory to output devices. It sends control signals to ALU and memory for carrying out the required operations.

A light pen is a pointing device that can be used to select anything on the computer screen by simply pointing at it or for drawing figures directly on the screen.

Answer

True

Reason — A light pen is a pointing device, basically a stylus, that can be used to select anything on the computer screen by simply pointing at it or for drawing figures directly on the screen.

RAM operates much faster than cache memory.

Answer

False

Reason — Cache memory is a small memory that operates much faster than the primary memory or RAM.

1 GB = 1024 KB.

Answer

False

Reason — 1 GB = 1024 MB and 1 MB = 1024 KB. Therefore, 1 GB = 1024 * 1024 KB.

An operating system acts as an interface between the user, computer hardware and software.

Answer

True

Reason — An operating system (OS) acts as an interface between the user, computer hardware and software. It manages hardware resources, facilitates user interaction, and provides necessary services for running application software.

A computer has the capacity to perform calculations and other logical functions, whereas a calculator only performs arithmetic and geometrical operations.

Answer

True

Reason — A computer can perform a wide range of tasks, including complex calculations, logical functions, data processing, and running various applications. In contrast, a calculator is primarily designed for arithmetic and simple geometrical operations.

Dot matrix printer uses laser technology to produce printed documents.

Answer

False

Reason — Laser printers use laser technology, while dot matrix printers use dots and strike an ink-soaked ribbon against paper to print, producing sound, and are called impact printers.

The primary memory unit stores data and instructions permanently.

Answer

False

Reason — Primary memory stores data and programs temporarily as long as they are being executed as primary memory has limited storage capacity.

ROM is volatile in nature.

Answer

False

Reason — ROM is permanent and non-volatile in nature.

External memory allows the permanent storage of large quantities of data.

Answer

True

Reason — External memory devices, such as hard drives, solid-state drives, and flash drives, provide a permanent storage solution for large quantities of data.

What is the full form of IPO?

1. Input Process Output
2. Input Print Output
3. Internet Print Output
4. Internet Process Output

Answer

Input Process Output

Reason — The full form of IPO is Input Process Output.

Which is the fastest memory device?

1. RAM
2. Register
3. Blu-ray Disc
4. Hard Disk

Answer

Register

Reason — Registers are the fastest memory device because they are small amounts of on-chip memory built directly into the CPU, providing immediate access to the data they store.

What is the full form of RAM?

1. Read Access Memory
2. Random Access Memory
3. Raw Access Memory
4. Right Access Memory

Answer

Random Access Memory

Reason — The full form of RAM is Random Access Memory.

ROM is a

1. volatile memory
2. non-volatile memory
3. Both (i) and (ii)
4. None of these

Answer

non-volatile memory

Reason — ROM is a permanent and non-volatile memory as it does not lose its contents when the power is switched off or interrupted.

What is an information?

1. Processed data
2. Collection of programs
3. Collection of instructions
4. None of these

Answer

Processed data

Reason — Information is defined as processed data, organized in a particular manner to generate meaningful piece of data.

Which of the following falls under utilities?

1. Text editor
2. Backup
3. Disk defragmenter
4. All of these

Answer

All of these

Reason — Utilities are system software designed to help analyze, configure, optimize, or maintain a computer. Text editors, backup tools, and disk defragmenters all fall under this category.

Which of the following are sub-units that make the CPU?

1. Control unit
2. ALU
3. Both (i) and (ii)
4. None of these

Answer

Both (i) and (ii)

Reason — CPU consists of Arithmetic Logic Unit (ALU), Control Unit (CU) and registers.

Which is/are a type(s) of OS?

1. Single-user OS
2. Multi-user OS
3. Time-sharing OS
4. All of these

Answer

All of these

Reason — Single-user OS, Multi-user OS, and Time-sharing OS are all types of operating systems (OS).

1 TB is equivalent to:

1. 2¹⁰ bytes
2. 2¹⁰ MB
3. 2¹⁰ GB
4. 2¹⁰ KB

Answer

2¹⁰ GB

Reason — 1 TB is equivalent to 2¹⁰ GB.

Storage of 1 KB means the following number of bytes:

1. 1000
2. 964
3. 1024
4. 1064

Answer

1024

Reason — 1 KB = 1024 bytes.

One Megabyte is equivalent to:

1. 2¹⁰ bytes
2. 2²⁰ bytes
3. 2³⁰ bytes
4. None of these

Answer

None of the above

Reason — 1 MB = 1024 KB = 1024 * 1024 bytes = 10,48,576 bytes.

Identify the input device(s):

1. Speaker
2. Printer
3. Keyboard
4. Plotter

Answer

Keyboard

Reason — A keyboard is an input device used to enter data in the form of letters, digits, and commands into the computer.

Which of the following is referred to as the brain of computer?

1. CPU
2. RAM
3. Hard Drive
4. ROM

Answer

CPU

Reason — The CPU, or Central Processing Unit, is referred to as the brain of the computer because it guides, directs, controls and governs all the processing that takes place inside the computer.

............... is capable of recognizing a pre-specified type of mark made with dark pencil or ink.

1. OCR
2. OMR
3. MICR
4. Barcode Reader

Answer

OMR

Reason — Optical Mark Reader (OMR) is capable of recognizing a pre-specified type of mark made with dark pencil or ink.

............... reads a sequence of lines of different heights and widths that are printed on various types of products.

1. OCR
2. OMR
3. MICR
4. Barcode Reader

Answer

Barcode Reader

Reason — A barcode is a collection or a sequence of lines of different heights and widths that are printed on various types of products.

............... uniquely identifies a person on the basis of physical or behavioural traits such as fingerprints, DNA, etc.

1. Touch screen
2. Biometric sensor
3. Optical character reader
4. QR code

Answer

Biometric sensor

Reason — Biometric sensor uniquely identifies a person on the basis of physical or behavioral traits such as eyes, fingerprints, DNA, etc.

Which smaller unit of CPU directs and coordinates all activities within it and determines the sequence in which instructions are executed, sending instruction sequence to other smaller units?

1. CU
2. ALU
3. Processor
4. All of these

Answer

CU

Reason — The Control Unit (CU) directs and coordinates all activities within the CPU and determines the sequence in which instructions are executed, sending instruction sequences to other smaller units.

Which of the following memory types will store data or information permanently?

1. RAM
2. Cache
3. Hard disk
4. All of these

Answer

Hard disk

Reason — A hard disk is a type of non-volatile memory, meaning it retains data or information permanently even when the computer is turned off.

Convert the following into Kilobytes:

2.7 GB = ............... Kilobytes

1. 2831155.2
2. 2764.8
3. 2831155.02
4. 2764.08

Answer

2831155.2

Reason — To convert gigabytes (GB) to kilobytes (KB), we use the following conversion factors:

1 GB = 1024 MB (megabytes)
1 MB = 1024 KB (kilobytes)

First, convert gigabytes to megabytes: 2.7 GB * 1024 = 2764.8 MB

Next, convert megabytes to kilobytes: 2,764.8 MB * 1024 = 2831155.2 KB

Therefore, 2.7 GB equals 2831155.2 kilobytes.

Spreadsheet is an example of ............... .

1. Application Software
2. System Software
3. Operating System
4. Utility Software

Answer

Application Software

Reason — Spreadsheet is a type of application software used for organizing, analyzing, and storing data in tabular form.

An operating system with a touch-based interface is ............... .

1. Android
2. iOS
3. Both 1 & 2
4. None of these

Answer

Both 1 & 2

Reason — Both Android and iOS are operating systems with touch-based interfaces.

Assertion (A): Computer is an electronic device that accepts input, processes it and displays the output.

Reasoning (R): Computer is a combination of hardware and software. Every task given to it follows IPO cycle.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer

Both A and R are true and R is the correct explanation of A.

Explanation
A computer is an electronic device that accepts a set of instructions in the form of a program, executes it and displays the output to the user. Computer is a combination of hardware and software. Every task given to a computer follows an Input → Process → Output Cycle (IPO cycle).

Assertion (A): Primary memory is the main memory inside computer that holds data, programs and instructions that are currently in use.

Reasoning (R): Secondary memory is used for permanent storage of data for future use.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer

Both A and R are true but R is not the correct explanation of A.

Explanation
Primary memory, also known as main memory, is the memory inside a computer that holds data, programs, and instructions that are currently in use. Secondary memory, also known as auxiliary memory, is used for permanent storage of data for future use.

Assertion (A): Cache memory is placed between CPU and main memory (RAM).

Reasoning (R): Cache memory stores frequently used data and instructions so that they are immediately available to the CPU.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer

Both A and R are true and R is the correct explanation of A.

Explanation
Cache memory is placed between the CPU and the main memory (RAM) to store frequently used data and instructions. By doing so, it makes this data available to the CPU very quickly, sending it directly to the CPU instead of the main memory. This significantly reduces access time, thereby improving the overall performance of the computer.

Assertion (A): Registers are the components that provide internal storage to the CPU.

Reasoning (R): User has direct access to CPU registers.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer

A is true but R is false.

Explanation
Registers are high-speed temporary storage areas found in the CPU. Registers work as per the instructions given by the control unit (CU), storing instructions and data. However, users do not have direct access to CPU register.

Assertion (A): Operating system is the most important utility software.

Reasoning (R): Utility Software are essential for maintenance and configuration of the computer system.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer

A is false but R is true.

Explanation
An operating system is not considered utility software, it is classified as system software. Utility software consists of programs that assist the computer by performing certain tasks that help in the proper maintenance and configuration of the computer.

Assertion (A): Operating system acts as an interface between a user and computer hardware.

Reasoning (R): Operating system manages all the resources of a computer.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer

Both A and R are true and R is the correct explanation of A.

Explanation
An operating system (OS) is a program that acts as an interface between the user and hardware of the computer. The OS helps to manage resources of the computer and optimize its performance.

Assertion (A): Three types of translators used in computing system are assemblers, compilers and interpreters.

Reasoning (R): A translator is used to convert program written in high-level language to binary language.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer

Both A and R are true and R is not the correct explanation of A.

Explanation
The translators can be of three types: assembler, compiler and interpreter. A translator is used to translate the program written in high-level language into machine code.

Define a computer.

Answer

A computer is an electronic device that accepts a set of instructions in the form of a program, executes it and displays the output to the user.

How does an ALU work?

Answer

The Arithmetic Logic Unit (ALU) makes all calculations and comparisons. The ALU performs the arithmetic (+, -, *, /) and logical (AND, OR, NOT, XOR) operations sent from the memory and returns the result to the memory. The result of the logical operations is either true or false and helps the computer in decision-making.

Briefly explain the working of a control unit.

Answer

The control unit controls the flow of data from input devices to memory and from memory to output devices. It controls and guides the interpretation, flow and manipulation of all data and information. It does not actually process the data, instead, it sends control signals to ALU and memory for carrying out the required operations.

Define hardware and software.

Answer

Hardware refers to the physical or tangible components of a computer system. Examples include the CPU, monitor, keyboard, mouse, hard drive, and printer.

Software is the code or a set of instructions necessary to operate/run the computer hardware. It is intangible component of a computer. Examples include operating systems, applications, and programming languages.

What is software?

Answer

Software is the collection of computer programs, procedures and documentation that performs different tasks in a computer system.

List some of the hardware in computer equipment.

Answer

Some hardware components found in computer equipment are:

1. CPU (Central Processing Unit)
2. Motherboard
3. RAM (Random Access Memory)
4. Keyboard
5. Mouse
6. Printer
7. Monitor

Explain the types of operating systems with examples.

Answer

Types of Operating systems are as follows:

Time-Sharing Operating System — Multiple users share system resources simultaneously, and the OS ensures that each user gets a slice of computing time. Examples, Unix.

Multi-User Operating System — Allows multiple users to access the computer resources simultaneously. Examples, Linux.

Single-User Operating System — Designed for one user to access the computer at a time. Examples, Windows 10, macOS.

"Hardware is of no use without software and software cannot be used without hardware." Explain.

Answer

Hardware refers to the physical components of a computer system, such as the CPU, memory, and storage devices, which provide the infrastructure for computing operations. However, without software — the programs and applications that instruct hardware how to function — these components cannot perform meaningful tasks. Conversely, software requires hardware to execute its instructions. Software encompasses operating systems, applications, and utilities that enable users to interact with computers and perform specific tasks. These programs rely on hardware to provide processing power, storage, and input/output capabilities necessary for running software effectively. Together, hardware and software make the computer system function.

How can software be classified? Name at least one software in each of the categories.

Answer

Depending on the mode of interaction with hardware and functions to be performed, software can be broadly classified into three categories:

1. System Software — System software refers to the programs that control internal computer operations and make best use of the hardware. For example, operating system, language translators etc.
2. Application Software — Application Software is the set of programs necessary to carry out operations for a specified application. For example, word processing software, spreadsheet software etc.
3. Utility Software — Utility software helps to manage, maintain and control computer resources. For example, text editor, antivirus software etc.

What is an operating system? Write names of any two popular operating systems.

Answer

An operating system is an integrated set of programs that manages various resources and the overall operations of a computer system. It is designed to support the various activities of the computer system in a systematic way.

For example, Microsoft Windows, Linux, etc.

Specify the measuring units of memory.

Answer

The measuring units of memory are bit (elementary unit), byte, Kilobyte, Megabyte, Gigabyte, Terabyte, Petabyte, Exabyte, Zettabyte, Yottabyte, Brontobyte, Geopbyte.

Identify the category (system, application, programming tool) of the following software:

(a) Compiler

(b) Assembler

(c) Ubuntu

(d) Text Editor

Answer

(a) Compiler — Programming Tool

(b) Assembler — Programming Tool

(c) Ubuntu — System Software

(d) Text Editor — Application Software

What do you mean by memory devices? Explain RAM and ROM.

Answer

Memory devices are hardware components that store data or program instructions for a computer.

1. RAM (Random Access Memory) — It is a read/write memory as it is possible to both read from and write to a location within RAM. It is used for primary storage in computers to hold active information of data and instructions. The RAM is a volatile memory as it does not store data and instructions permanently and loses its contents when the power is switched off or interrupted. RAM provides faster access than secondary memory with less memory access time. The RAM chip in a computer can be categorized into two types:

   1. Static RAM (SRAM)
   2. Dynamic RAM (DRAM)

2. ROM (Read-Only Memory) — It is a read-only memory, i.e., the data and instructions are placed in the ROM at the time of its manufacturing and cant be changed thereafter. It is a permanent and non-volatile memory as it does not lose its contents when the power is switched off or interrupted. It is slower than RAM and is used to hold certain essential instructions to check basic hardware components such as booting, procedures to load operating system and frequently needed functions. The different types of ROM available are:

   1. PROM (Programmable Read-Only Memory)
   2. EPROM (Erasable Programmable Read-Only Memory)
   3. EEPROM (Electrically Erasable Programmable Read-Only Memory)

What are output devices? Give some examples.

Answer

Output devices are the devices that produce the output generated by the CPU in human understandable form, such as audio, video, text or hard copy, viz. printed documents.

For example: Visual Display Unit (VDU)/Monitor, LCD Screen, LED Screen, OLED, Printer, Speakers, Plotters etc.

List different types of impact printers.

Answer

The different types of impact printers are as follows:

1. Dot Matrix Printers
2. Daisy Wheel Printers
3. Line Printers
4. Band Printers
5. Drum Printers

Briefly explain the working of a laser printer.

Answer

Laser printers use laser technology to produce printed documents. They use a dry form of ink called toner which is made up of tiny particles. They are very fast and are used for high-quality prints.

What is the use of a light pen?

Answer

A light pen is a pointing device that can be used to select anything on the computer screen by simply pointing at it or for drawing figures directly on the screen.

Given below are some features of computer memories—RAM and ROM. List the below-given features under RAM or ROM:

(a) Non-volatile Memory

(b) Content can't be changed

(c) Volatile Memory

(d) Can be written to and read from

Answer

Expand the following terms:

(a) ALU

(b) GUI

Answer

(a) ALU — Arithmetic and Logic Unit

(b) GUI — Graphical User Interface

Explain in brief the working of a touch screen.

Answer

Touch screen is a type of display screen which allows interaction with computer through a touch-sensitive transparent panel covering the entire screen without any intermediate device. The touch screen uses a technology that enables the users to touch the screen with fingers to select objects.

What are plotters? List the different types of plotters.

Answer

Plotters are output devices that are used for producing high quality images, engineering drawings, architectural blueprints etc.

The different types of plotters are as follows:

1. Pen Plotters
2. Flatbed Plotters
3. Drum Plotters

Check the size of RAM and HDD of a computer in your school. Make a table and write their size in Bytes, Kilobytes, Megabytes and Gigabytes.

Answer

The table with sizes for RAM and HDD of a computer:

List all the secondary storage devices available at your school or home.

Answer

The secondary storage devices available at school or home are as follow

1. Hard Disk Drives (HDDs)
2. Solid State Drives (SSDs)
3. USB Flash Drives (Pen Drives)
4. External Hard Drives
5. Compact Discs (CDs)
6. Digital Versatile Discs (DVDs)
7. Blu-ray Discs
8. Memory Cards (SD cards, microSD cards)

Which operating system is installed on your computer at home or in school?

Answer

The operating system installed on the computer at home is Windows 11, while the one installed at school is Windows 10.

Convert the following into bytes:

(a) 2 MB

(b) 3.7 GB

(c) 1.2 TB

Answer

(a) 2 MB — 2 MB * 1024 KB/MB * 1024 bytes/KB = 2 * 1024 * 1024 = 2,097,152 bytes

(b) 3.7 GB — 3.7 GB * 1024 MB/GB * 1024 KB/MB * 1024 bytes/KB = 3.7 * 1024 * 1024 * 1024 = 3,973,078,528 bytes

(c) 1.2 TB — 1.2 TB * 1024 GB/TB * 1024 MB/GB * 1024 KB/MB * 1024 bytes/KB = 1.2 * 1024 * 1024 * 1024 * 1024 = 1,319,843,208,192 bytes

Identify the type of software:

(a) The software acts as an interface between a user and the hardware.

(b) It converts the program written in HLL into machine language by converting and executing it line by line.

Answer

(a) Operating System

(b) Interpreter

Write down the type of memory needed to do the following:

1. To store data permanently,
2. To execute a program,
3. To store instructions which cannot be overwritten.

Answer

1. To store data permanently — Secondary memory (e.g., Hard Disk Drive (HDD), Solid State Drive (SSD), Flash Memory)
2. To execute a program — Random Access Memory (RAM)
3. To store instructions which cannot be overwritten — Read-Only Memory (ROM)

How is an interpreter different from compiler on these parameters?

(a) Memory requirement during translation

(b) Memory requirement after translation

(c) Number of instructions translated

Answer

(a) Memory requirement during translation — Interpreter requires less memory during translation, as it translates and executes code line by line. Compiler requires more memory during translation, as it translates the entire program at once before execution.

(b) Memory requirement after translation — Interpreter continues to require memory after translation, as it needs to re-translate every time the program is run. Compiler requires less memory after translation, as it produces an executable file that can be run independently.

(c) Number of instructions translated — Interpreter translates and executes one instruction at a time. Compiler translates the entire set of instructions at once, producing a complete machine code program.

What is the major difference between optical and magnetic discs?

Answer

Optical Discs use laser technology to read and write data. The data is encoded on the disc surface as tiny pits and lands, which are read by a laser beam.

Magnetic Discs use magnetic fields to store data. The data is recorded on a magnetic surface, such as that found in hard disk drives, in the form of magnetic patterns.

List the differences between a CD and a DVD.

Answer

Explain the statement, "Functioning of a computer is similar to the way the human brain functions."

Answer

The statement "Functioning of a computer is similar to the way the human brain functions" compares how both systems process information. Computers use input devices like keyboards and mice to receive data, and output devices like monitors and printers to present results. Similarly, the human brain receives input through sensory organs such as the eyes, ears, and skin, and produces responses through actions and speech. Both systems use internal processes—computers use the CPU and memory for data handling, while the brain processes sensory information and stores memories.

Explain in brief the basic architecture of a computer.

Answer

A computer system comprises of five basic components:

1. Input Unit — An input unit takes the input and converts it into binary form so that it can be understood by the computer. For example, keyboard, mouse etc.
2. Output Unit — It converts the output in binary form to human readable form. For example, monitor, speakers etc.
3. Central Processing Unit (CPU) — It is responsible for processing the data and instructions. It consists of two parts:
   1. Arithmetic and Logic Unit (ALU) — It performs all the four arithmetic operations (addition, subtraction, multiplication and division) and some logical operations (less than, greater than, less than equal to, greater than equal to, equal to, not equal to).
   2. Control Unit (CU) — It acts as a supervisor by controlling and guiding the operation taking place.
4. Primary Memory — It is the internal volatile­ memory where data and instructions are stored during processing. It is of two types: Random Access Memory (RAM) and Read Only Memory (ROM).
5. Secondary Storage Unit — It refers to the external storage devices which provide permanent memory to the computer system. For example, hard disk, compact disk, flash drive etc.

What is an input unit? Give its significance.

Answer

An input unit takes the input and converts it into binary form which is directly understood by the computer.

Computers only understand binary language that uses just two symbols: 1 for ON and 0 for OFF. The input unit translates raw data from external sources into binary language that the computer understands. Without this conversion, the computer would not be able to understand or process the data provided.

List and briefly explain all the components of a CPU.

Answer

There are mainly three components of a CPU:

1. Arithmetic and Logical Unit (ALU) — All calculations and comparisons are made in this unit. The ALU performs the arithmetic (+, -, *, /) and logical (AND, OR, NOT, XOR) operations sent from the memory, performs specific operations (addition, subtraction etc) and the result is returned to the memory. The result of the logical operations is either true or false and helps the computer in decision-making.

2. Control Unit (CU) — The CU controls the flow of data from input devices to memory and from memory to output devices. It controls and guides the interpretation, flow and manipulation of all data and information. It does not actually process the data, instead, it sends control signals to ALU and memory for carrying out the required operations.

3. Registers — These are high-speed temporary storage areas found in CPU. Registers work as per the instructions given by the control unit (CU), storing instructions and data immediately required for performing an operation. The CPU places the highest priority jobs/data inside registers for faster execution/processing. Registers can be of different sizes (16 bits, 32 bits, 64 bits and so on) and each register inside the CPU has a specific function like storing data, storing an instruction, storing address of a location in memory etc.

Why is a control unit referred to as the central controller of a computer?

Answer

A control unit is referred to as the central controller of a computer because it controls the flow of data from input devices to memory and from memory to output devices. It controls and guides the interpretation, flow, and manipulation of all data and information, sending control signals to the Arithmetic Logic Unit (ALU) and memory to execute the required operations effectively.

Does an ALU work independently or in coordination with some other unit? Give reasons.

Answer

Arithmetic Logic Unit (ALU) does not work independently; it operates in coordination with the control unit and memory. The control unit fetches instructions from memory and decodes them, directing the ALU to perform specific operations such as addition, subtraction, or logical comparisons. The results produced by the ALU are then stored back in memory or used by other components of the computer system.

Compare data and information.

Answer

How does an output unit work? Give examples of some output devices.

Answer

The output unit consists of output devices attached to the computer. These devices produce output generated by the CPU in a form that is readable and understandable by humans. The CPU processes data in binary form, and the output unit translates this data into text, images, audio, or other formats suitable for human interpretation.

Examples: Monitor, Printer, Speakers, Plotters etc.

What is the role of memory in the functioning of a computer?

Answer

The memory of the computer is like a predefined working space where it temporarily keeps information and data to facilitate its working. When the task is executed or finished, it clears the memory and this memory space is available for the next task to be executed or performed.

Draw the block diagram of a computer system. Briefly write about the functionality of each component.

Answer

The block diagram of the computer system is shown below:

1. Input Unit — An input unit takes/accepts input and converts it into binary form so that it can be understood by the computer. The computer input constitutes data and instructions.

2. Central Processing Unit — CPU is the control centre or brain of a computer. It guides, directs, controls and governs all the processing that takes place inside the computer. There are mainly three components of a CPU:

   1. Arithmetic and Logical Unit (ALU) — The ALU performs the arithmetic (+, -, *, /) and logical (AND, OR, NOT, XOR) operations sent from the memory, performs specific operations (addition, subtraction etc) and the result is returned to the memory.

   2. Control Unit (CU) — The CU controls the flow of data from input devices to memory and from memory to output devices.

   3. Registers — These are high-speed temporary storage areas found in CPU. Registers work as per the instructions given by the control unit (CU), storing instructions and data immediately required for performing an operation.

3. Memory Unit — Memory unit is used as a storage unit for program as well as data. The memory can be both primary and secondary depending upon its location in the computer system. The primary memory, also termed as main memory, is directly accessible to the CPU since all the work is done in the RAM and later on gets stored on the secondary storage. On the contrary, the secondary memory, also known as auxiliary memory, can be accessed by the CPU through input-output controllers or units.

4. Output Unit — Output unit is formed by the output devices attached to the computer. Output devices produce the output generated by the CPU in human readable form.

Compare volatile memory and non-volatile memory.

Answer

Define primary storage devices. List their types.

Answer

Primary storage devices refer to the main memory in a computer that is directly accessible by the CPU. This memory is used to temporarily store data and instructions that the CPU needs while performing tasks.

The primary storage devices are classified into two types:

1. Random Access Memory (RAM)
2. Read-Only Memory (ROM)

What do you mean by a mouse? List its types.

Answer

A mouse is a pointing device with a roller at its base, used for moving a pointer on a computer monitor.

The different types of mouse are as follows:

1. Mechanical Mouse
2. Opto-Mechanical Mouse
3. Optical Mouse
4. Wireless Mouse
5. Touchpad Mouse

What is a barcode? Why is a bar code reader used?

Answer

A barcode is a collection or a sequence of lines of different heights and widths that are printed on various types of products. The machine that reads these barcodes is called a barcode reader. A barcode reader is used to convert the information encoded in a barcode into a digital format that can be processed by a computer system.

Explain, in brief, inkjet and laser jet printers.

Answer

1. Inkjet Printers — An inkjet printer is the most common type of low-cost printer. It uses the technique of spreading quick dry ink on paper. The ink is stored in the form of cartridges of different colours. These printers generate high quality prints and are ideal for small offices and homes.

2. Laser Jet Printers — These printers use laser technology to produce printed documents. These are very fast printers and are used for high quality prints.

What is a plotter? Give the benefits and limitations of using plotters.

Answer

Plotters are the output devices that are used for producing high quality images, engineering drawings, architectural blueprints, maps etc.

Benefits of using Plotters are as follows:

1. Plotters provide high-quality output.
2. They can handle large paper sizes, making them suitable for creating large-scale diagrams and posters.
3. Plotter-produced documents often have better longevity and clarity for detailed and technical illustrations.

Limitations of using Plotters are as follows:

1. Plotters are generally more expensive than standard printers.
2. Plotters can be slower compared to modern printers, especially when producing complex or large-format drawings.
3. They require specialized software and may need more technical expertise to operate effectively.

Explain any three types of input devices.

Answer

The three types of input devices are as follows:

1. Keyboard — A keyboard is the input device which directly enters the data in the form of letters, digits and commands into the computer. QWERTY keyboard is the commonly-used keyboard.

2. Mouse — A mouse is a pointing device with a roller at its base, used for moving a pointer on a computer monitor. It converts the movements of the user's hand into a unique set of binary digits representing the position of the mouse at a particular instant. When a user moves a mouse across a flat surface, the pointer moves in the direction of the mouse's movement.

3. Light Pen — A light pen is a pointing device that can be used to select anything on the computer screen by simply pointing at it or for drawing figures directly on the screen. It consists of a photocell mounted on a pen-shaped tube called stylus. It is capable of sensing a position on the screen when its tip touches the screen. Clicking is performed by pressing the pen on the screen. A light pen is mostly used by engineers, architects or designers.

Define VDU. Name its two types.

Answer

A Visual Display Unit (VDU) commonly known as monitor, is the most common device for displaying the output of the computer-processed information.

The two types of VDU are as follows:

1. CRT (Cathode Ray Tube)
2. LCD (Liquid Crystal Display)

Give the difference between an impact and a non-impact printer.

Answer

Discuss the following devices:

(a) Light Pen

(b) Graphic Tablet

(c) CD-ROM

(d) DVD

Answer

(a) Light Pen — A light pen is a pointing device that can be used to select anything on the computer screen by simply pointing at it or for drawing figures directly on the screen. It consists of a photocell mounted on a pen-shaped tube called stylus. It is capable of sensing a position on the screen when its tip touches the screen. Clicking is performed by pressing the pen on the screen. A light pen is mostly used by engineers, architects or designers.

(b) Graphic Tablet — A graphic tablet is an input device with a touch-sensitive surface that allows users to create digital art and designs. It comes with a stylus that mimics traditional drawing tools. Graphic tablets connect to computers via USB or Bluetooth, facilitating precise digital artwork, photo editing, 3D modelling, and handwriting.

(c) CD-ROM — It is a thin optical disc which is commonly used to store audio and video data. The capacity of a standard 120 mm CD is 700 MB. Originally, CD-ROM drives had transfer rate of only 150 KB/s which was very low. The latest CD-ROM drives can transfer up to 10800 KB/sec.

(d) DVD — Digital Versatile Disc or Digital Video Disc is an optical disc storage device. It can be recorded on one or both sides. Its capacity may range from 4.7 GB to 17.08 GB.

Discuss the classification of digital computers.

Answer

Digital computers can be classified into four major categories based on their size, power, and functionality:

1. Microcomputers (Personal Computers) — These are small, relatively inexpensive computers designed for individual use. They have a microprocessor, memory (RAM and ROM), and storage devices. Examples: Desktop computers, laptops, tablets, and smartphones.

2. Minicomputers — These are mid-sized computers that are more powerful than microcomputers but less powerful than mainframes. They can support multiple users simultaneously and are used in small to medium-sized businesses. Examples: DEC PDP-11.

3. Mainframe Computers — These are large, powerful, and expensive computers used mainly by large organizations for critical applications, bulk data processing, and large-scale transaction processing. They can handle and process vast amounts of data simultaneously and can support hundreds or thousands of users at once. Examples: IBM zSeries.

4. Supercomputers — These are the most powerful computers in terms of processing capacity and are used for highly complex computations. They are used for scientific and engineering applications, like weather forecasting, nuclear simulations, and complex biological computations. Examples: Cray XT5, IBM Summit.

Discuss secondary storage devices in detail.

Answer

Some of the common secondary storage devices are as follows:

1. Hard Disk — A hard-disk is a non-volatile, high capacity storage device ranging from 1 Gigabyte to several Terabytes. It consists of solid rounded disks, packed on one another, made up of a magnetic material and sealed inside a case. In a hard disk, data is stored on spinning magnetic disks called platters. Each platter is divided into tracks and sectors.

2. Blu-ray Disc (BD) — A Blu-ray Disc is a high-capacity optical disk medium developed for recording, rewriting and playing back high-definition video. It uses blue laser that permits large amount of data to be stored at a greater density. They support higher resolutions and more advanced video and audio formats as compared to DVDs.

3. Compact Disc (CD) — It is a thin optical disc which is commonly used to store audio and video data. The capacity of a standard 120 mm CD is 700 MB. Originally, CD-ROM drives had transfer rate of only 150 KB/s which was very low. The latest CD-ROM drives can transfer up to 10800 KB/sec.

4. Magnetic Tapes — In this, magnetic coatings are stored as data on a thin tape. Data read/write speed is slower because of sequential access. They are convenient, secure and affordable.

5. DVD — Digital Versatile Disc or Digital Video Disc is an optical disc storage device. It can be recorded on one or both sides. Its capacity may range from 4.7 GB to 17.08 GB.

6. USB Pen Drive — This is a small, portable memory which can be plugged into a computer with USB Port. A pen drive's capacity is less than that of the hard disk but much higher than a floppy or CD. It is more reliable also. Pen drives have a storage capacity of 2GB, 4GB, 8GB, 16GB, 32GB and 64GB, up to 2TB.

7. Memory Cards — These are data storage devices, also called Flash memory cards. They are mainly used with digital cameras, computers, mobile phones, music players, video game consoles etc. They offer high recording ability with power-free storage. Memory cards come with a storage capacity of 8GB, 16GB, 32GB, 64GB and 128GB, up to 1.5TB.

What are memory cards? Discuss their types.

Answer

Memory cards are small, portable storage devices used to store data, such as photos, videos, music, and other files, in electronic devices like cameras, smartphones, tablets, and laptops and are also called flash cards.

The types of memory cards are as follows:

1. Secure Digital (SD) cards — SD cards are widely used in cameras, smartphones, and other devices. They come in various capacities, from a few hundred megabytes to several gigabytes.

2. MicroSD cards — A smaller version of SD cards, microSD cards are used in devices like smartphones, tablets, and action cameras.

3. CompactFlash (CF) cards — CF cards are larger and faster than SD cards, making them suitable for professional photographers and high-end cameras.

Explain the following:

(a) Assembler

(b) Compiler

(c) Interpreter

Answer

(a) Assembler — Assembler is used to translate the program written in assembly language into machine code. The input of assembler is a source program that contains assembly language called mnemonics. The output generated by the assembler is the object code or machine code which is understandable by the computer.

(b) Compiler — The language processor that translates the complete source program as a whole in one go into machine code is called compiler.

(c) Interpreter — The language processor that translates a single statement of source program into machine code and executes it immediately before moving on to the next line is called interpreter. If there is an error in the statement, the interpreter terminates its translating process at that statement and displays an error message.

What is the need for secondary memory?

Answer

Secondary memory provides permanent storage for data and information needed for future use. It allows users to store large amounts of data systematically and retrieve it as required. Additionally, it retains data and programs even when the computer is turned off.

What is the need of RAM and ROM?

Answer

RAM (Random Access Memory) is needed for temporary storage of data and instructions that the CPU uses actively. It provides faster access than secondary memory with less memory access time.

ROM (Read-Only Memory) is needed for permanent storage of data. It is used to hold certain essential system instructions to check basic hardware components such as booting, procedures to load operating system and frequently needed functions.

Name the software required to make a computer functional. Write down its two primary services.

Answer

The software required to make a computer functional is the Operating System (OS).

Its two primary services are:

1. Resource Management
2. Process Management