Samacheer Kalvi 11th Computer Science Solutions Chapter 3 Computer Organization

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Tamilnadu Samacheer Kalvi 11th Computer Science Solutions Chapter 3 Computer Organization

Samacheer Kalvi 11th Computer Science Computer Organization Text Book Back Questions and Answers

PART – 1
I. Choose The Correct Answer

11th Computer Science Chapter 3 Book Back Answers Question 1.
Which of the following is said to be the brain of a computer?
(a) Input devices
(b) Output devices
(c) Memory device
(d) Microprocessor
Answer:
(d) Microprocessor

Computer Science Chapter 3 Answers Question 2.
Which of the following is not the part of a microprocessor unit?
(a) ALU
(b) Control unit
(c) Cache memory
(d) register
Answer:
(c) Cache memory

Samacheer Kalvi Guru 11th Computer Science Question 3.
How many bits constitute a word?
(a) 8
(b) 16
(c) 32
(d) determined by the processor used
Answer:
(d) determined by the processor used

11th Computer Science Samacheer Solutions Question 4.
Which of the following device identifies the location when address is placed in the memory address register?
(a) Locator
(b) encoder
(c) decoder
(d) multiplexer
Answer:
(c) decoder

Samacheer Kalvi 11th Computer Science Question 5.
Which of the following is a CISC processor?
(a) Intel P6
(b) AMD K6
(c) Pentium III
(d) Pentium IV
Answer:
(c) Pentium III

Class 11 Computer Science Chapter 3 Notes Question 6.
Which is the fastest memory?
(a) Hard disk
(b) Main memory
(c) Cache memory
(d) Blue – Ray disc
Answer:
(c) Cache memory

Computer Organization Class 11 Question 7.
How many memory locations are identified by a processor with 8 bits address bus at a time?
(a) 28
(b) 1024
(c) 256
(d) 8000
Answer:
(c) 256

Samacheer Kalvi 11th Computer Science Guide Question 8.
What is the capacity of 12 cm diameter DVD with single sided and single layer?
(a) 4.7 GB
(b) 5.5 GB
(c) 7.8 GB
(d) 2.2 GB
Answer:
(a) 4.7 GB

11th Samacheer Computer Science Book Back Answers Question 9.
What is the smallest size of data represented in a CD?
(a) blocks
(b) sectors
(c) pits
(d) tracks
Answer:
(c) pits

Samacheer Kalvi.Guru 11th Computer Science Question 10.
Display devices are connected to the computer through.
(a) USB port
(b) PS/2 port
(c) SCSI port
(d) VGA connector
Answer:
(d) VGA connector

PART – 2
II. Short Answers

Samacheerkalvi.Guru Computer Science Question 1.
What are the parameters which influence the characteristics of a microprocessor?
Answer:
A Microprocessor’s performance depends on the following characteristics:

  • Clockspeed
  • Instruction set
  • Word size

Computer Science Chapter 3 Question 2.
What is an instruction?
Answer:
Instruction is a command which is given to the computer to perform an operation on a piece of data.

Samacheer Kalvi Guru 11 Computer Science Question 3.
What is a program counter?
Answer:
The Program Counter (PC) is a special register in the CPU which always keeps the address of the next instruction to be executed.

Computer Science Class 11 Chapter 3 Question 4.
What is HDMI?
Answer:
HDMI (High Definition Multimedia Interface is an audio/video interface which transfer the the uncompressed video and audio data from a video controller, to a compatible computer monitor, LCD projector, digital television, etc.

Computer Organization Questions And Answers Question 5.
Which source is used to erase the content of a EPROM?
Answer:
EPROM retains its contents until it is exposed to ultraviolet light. The ultraviolet light clears its contents.

PART – 3
III. Explain in Brief

Class 11 Computer Science Chapter 3 Question 1.
Differentiate Computer Organisation from Computer Architecture.
Answer:
Computer architecture deals with the engineering considerations involved in designing a computer.
The Computer Organization deals with the hardware components that are transparent to the programmer.

11th Computer Science Answers Question 2.
Classify the microprocessor based on the size of the data.
Answer:
Depending upon the size of the data the microprocessor can be classified as

  1. 8 bit microprocessor
  2. 16 bit microprocessor
  3. 4 bit microprocessor
  4. 32 bit microprocessor
  5. 64 bit microprocessor.

Computer Chapter 3 Question Answer Question 3.
Write down the classifications of microprocessors based on the instruction set.
Answer:
The two types of microprocessors based on their instruction sets are
i) Reduced Instruction Set Computers (RISC)
RISC stands for Reduced Instruction Set Computers. They have a small set of highly optimized instructions. Complex instructions are also implemented using simple instructions, thus reducing the size of the instruction set.
Examples of RISC processors are Pentium IV, Intel P6, AMD K6, and K7.

ii) Complex Instruction Set Computers (CISC)
CISC stands for Complex Instruction Set Computers. They support hundreds of instructions. Computers supporting CISC can accomplish a wide variety of tasks, making them ideal for personal computers.
Examples of CISC processors are Intel 386 & 486, Pentium, Pentium II and III, and Motorola 68000.

Samacheer Kalvi 11th Computer Science Book Back Answers Question 4.
Differentiate PROM and EPROM.
Answer:
PROM:

  • Can be Programmed only once.
  • This has Permanent memory.
  • Enclosed in plastic package so that not visible to UV light.
  • Uses high Voltage.

EPROM:

  • It is reusable and can be programmed multiple times.
  • EPROMs memory can be erased using UV light.
  • EPROMs are fused with quartz window.
  • Also use high Voltage but not enough to alter the semiconductor layer permanently.

Computer Science Samacheer Kalvi Question 5.
Write down the interfaces and ports available in a computer.
Answer:
The various types of ports interfaces are:

  • Serial Port: To connect the external devices, found in old computers.
  • Parallel Port: To connect the printers, found in old computers.
  • USB Ports: To connect external devices like cameras, scanners, mobile phones, external hard disks, and printers to the computer.
  • VGA Connector: To connect a monitor or any display device like an LCD projector.
  • Audio Plugs: To connect sound speakers, microphones, and headphones.
  • PS/2 Port: To connect mouse and keyboard to PC.
  • SCSI Port: To connect the hard disk drives and network connectors.

11th Computer Science Answer Question 6.
Differentiate CD and DVD.
Answer:
CD:

  • CD stands for Compact Disc.
  • Can store up to 700 MB.
  • CD’s are single sided.
  • Due to capacity constraint, CD’s cannot store movies of good quality.
  • CD players cannot play DVD’s.

DVD:

  • DVD stands for Digital Versatile Disc.
  • Capacity of DVD is 4.7 GB of data.
  • DVD’s are single or double sided.
  • DVD’s are used for storing movies with good quality.
  • DVD players can play CD’s.

Samacheer Kalvi Guru Computer Science Question 7.
How will you differentiate a flash memory and an EEPROM?
Answer:
Flash memory:

  • It is faster.
  • Flash memory is read/write memory.
  • Flash memory can store 4GB to 2TB of data.
  • Flash memory is used in PDA’S, Digital camera to store data.

EEPROM:

  • It is slower.
  • EEPROM is read only memory.
  • EEPROM can store only less data.
  • It is used to store critical programs.

PART – 4
IV. Explain in Detail

11th Samacheer Kalvi Computer Science Question 1.
Explain the characteristics of a microprocessor.
Answer:
A Microprocessor’s performance depends on the following characteristics:

  • Clock speed
  • Instruction set
  • Word size

a) Clock Speed:
Every microprocessor has an internal clock that regulates the speed at which it executes instructions. The speed at which the microprocessor executes instructions ¡s called the clock speed. Clock speed is measured in MHz (MegaHertz) or in GHz (Giga Hertz).

b) Instruction Set
A command which is given to a computer to perform an operation on data is called an instruction. A basic set of machine-level instructions that a microprocessor is designed to execute ¡s called an instruction set.

This instruction set carries out the following types of operations:

  • Data transfer
  • Arithmetic operations
  • Logical operations
  • Control flow
  • Input/output

c) Word Size
The number of bits that can be processed by a processor in a single instruction is called its word size. Word size determines ‘the amount of RAM that can be accessed by a microprocessor at one time and the total number of pins on the microprocessor, total number of input and output pins, in turn, determines the architecture of the microprocessor.

Computer Science Solutions Question 2.
How the read and write operations are performed by a processor? Explain.
Answer:

  1. The Central Processing Unit(CPU) has a Memory Data Register (MDR) and a Memory Address Register (MAR).
  2. The Memory Data Register (MDR) keeps the data which is transferred between the Memory and the CPU. The Program Counter (PC) is a special register in the CPU which always keeps the address of the next instruction to be executed.
  3. The Arithmetic and Logic unit of CPU places the address of the memory to be fetched, into the Memory Address Register.
  4. A bus is a collection of wires used for communication between the internal components of a computer.
  5. The address bus is used to point a memory location. A decoder, a digital circuit is used to point to the specific memory location where the word can be located.
  6. The address register is connected with the address bus, which provides the address of the instruction. A data bus is used to transfer data between the memory and the CPU.
  7. The data bus is bidirectional and the address bus is unidirectional. The control bus controls both read ana write operations.
  8. The read operation fetches data from memory and transfers to MDR. A single control line performs two operations like Read/Write using lor 0.
  9. Also, the write operation transfers data from the MDR to memory. This organisation is shown below.
    11th Computer Science Chapter 3 Book Back Answers Samacheer Kalvi
  10. The word in the RAM has the same size (no. of bits) as the Memory Data Register (MDR). If the processor is an 8-bit processor like Intel 8085, its MDR and the word in the RAM both have 8 bits.
  11. If the size of the MDR is eight bits, which can be connected with a w7ord in the memory which is also eight bits size. The data bus has eight parallel wires to transfer data either from MDR to word or word to MDR based on the control(Read or write).
  12. This control line is labeled as R/W, which becomes 1 means READ operation and 0 means WRITE operation.
    Computer Science Chapter 3 Answers Samacheer Kalvi
  13. These pictures show the contents of MDR and the word before and after the READ operation.
  14. The read operation transfers the data(bits) from word to Memory Data Register.
  15. The write operation transfers the data(bits) from Memory Data Register to word.

Samacheer Kalvi 11th Computer Question 3.
Arrange the memory devices in ascending order based on the access time.
Answer:
A memory is just like a human brain. It is used to store data and instructions. Computer memory is the storage space in the computer, where data and instructions are stored. There are two types of accessing methods to access (read or write) the memory. They are sequential access and random access. In sequential access, the memory is accessed in an orderly manner from starting to end. But, in random access, any byte of memory can be accessed directly without navigating through previous bytes. Different memory devices are arranged according to the capacity.
Samacheer Kalvi Guru 11th Computer Science

Question 4.
Explain the types of ROM.
Answer:
11th Computer Science Samacheer Solutions

Types of ROM
Read-Only Memory (ROM):
Read-Only Memory refers to special memory in a computer with pre-recorded data at manufacturing time which cannot be modified. The stored programs that start the computer and perform diagnostics are available in ROMs. ROM stores critical programs such as the program that boots the computer. Once the data has been written onto a ROM chip, it cannot be modified or removed and can only be read. ROM retains its contents even when the computer is turned off. So, ROM is called non-volatile memory.

Programmable Read-Only Memory (PROM):
Programmable read-only memory is also a non-volatile memory on which data can be written only once. Once a program has been written onto a PROM, it remains there forever. Unlike the main memory, PROMs retain their contents even when the computer is turned off.

The PROM differs from ROM. PROM is manufactured as blank memory, whereas a ROM is programmed during the manufacturing process itself. A PROM programmer or a PROM burner is used to write data to a PROM chip. The process of programming a PROM is called burning the PROM.

Programmable Read-Only Memory (EPROM):
Erasable Programmable Read-Only Memory is a special type of memory which serves as a PROM, but the content can be erased using ultraviolet rays. EPROM retains its contents until it is exposed to ultraviolet light. The ultraviolet light clears its contents, making it possible to reprogram the memory.
An EPROM differs from a PROM, PROM can be written only once and cannot be erased.

Electrically Erasable Programmable Read-Only Memory (EEPROM):
Electrically Erasable Programmable Read-Only Memory is a special type of PROM that can be erased by exposing it to an electrical charge. Like other types of PROM, EEPROM retains its contents even when the power is turned off. Comparing with all other types of ROM, EEPROM is slower in performance.

Samacheer Kalvi 11th Computer Science Computer Organization Additional Questions and Answers

PART – 1
I. Choose the correct answer

Question 1.
Computer organization deals with the __________ of a computer.
a) software
b) hardware
c) freeware
d) None of these
Answer:
b) hardware

Question 2.
The speed at which the microprocessor executes instructions is called ……………….
(a) Instruction set
(b) word size
(c) clock speed
(d) control flow
Answer:
(c) clock speed

Question 3.
__________ deals with the engineering considerations involved in designing a computer.
a) Computer organization
b) Computer architecture
c) Computer Science
d) None of these
Answer:
b) Computer architecture

Question 4.
The main memory is otherwise called as ……………….
(a) cache memory
(b) main memory
(c) hard disk
(d) random access memory
Answer:
(d) random access memory

Question 5.
The __________ is the major component of a computer.
a) Storage device
b) CPU
c) Cache memory
d) All the above
Answer:
b) CPU

Question 6.
………………. is a high – density optical disc similar to DVD.
(a) Blu – Ray disc
(b) digital versatile disc
(c) flash memory devices
(d) compact disc
Answer:
(a) Blu – Ray disc

Question 7.
The microprocessors were first introduced in early __________
a) 1960
b) 1950
c) 1970
d) 1980
Answer:
c) 1970

Question 8.
………………. is an electronic (solid-state) non-volatile computer storage medium that can be electrically erased and reprogrammed.
(a) main memory
(b) flash memory
(c) Blu – Ray disc
(d) USB
Answer:
(b) flash memory

Question 9.
The __________ is a programmable multipurpose silicon chip.
a) Transistor
b) Vacuum tube
c) Microprocessor
d) None of these
Answer:
c) Microprocessor

Question 10.
………………. is commonly used to measure wave frequencies.
(a) Hertz
(b) internal memory
(c) RAM
(d) ALU
Answer:
(a) Hertz

Question 11.
The microprocessor is made up of __________ main units.
a) 5
b) 4
c) 2
d) 3
Answer:
d) 3

Question 12.
Computer architecture deals with ……………….
(a) designing the computer
(b) input devices
(c) output devices
(d) memory
Answer:
(a) designing the computer

Question 13.
__________ perform arithmetic and logical instructions based on computer instructions.
a) ALU
b) registers
c) control unit
d) All the above
Answer:
a) ALU

Question 14.
Which one of the following is a programmable multipurpose silicon chip and are driven by clock pulses?
(a) Hardware
(b) Memory
(c) Microprocessor
(d) Clock
Answer:
(c) Microprocessor

Question 15.
__________ is used to hold the instruction and data for the execution of the processor.
a) ALU
b) registers
c) control unit
d) All the above
Answer:
d) All the above

Question 16.
How many types of system buses are available?
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
(b) 3

Question 17.
The system __________is a bunch of wires that serve as communication channels between the microprocessor and other devices.
a) bus
b) cable
c) port
d) None of these
Answer:
a) bus

Question 18.
Which one of the following bus serves as a communication channel between the microprocessor and other devices.
(a) Address bus
(b) Data bus
(c) Control bus
(d) Process bus
Answer:
(c) Control bus

Question 18.
__________is a type of bus.
a) address bus
b) data bus
c) control bus
d) All the above
Answer:
d) All the above

Question 20.
An average human ear can detect sound waves between ……………….
(a) 20 to 200 Hz
(b) 20 to 2000 Hz
(c) 20 to 20000 Hz
(d) 20 to 200000 Hz
Answer:
(c) 20 to 20000 Hz

Question 21.
__________ is the standard unit of measurement used for measuring frequency.
a) Hertz
b) Pixels
c) Bits
d) Bytes
Answer:
a) Hertz

Question 22.
Which among the following is not an operation carried out Instruction set?
(a) Arithmetic operations
(b) Logical operations
(c) Control flow
(d) Bitwise operations
Answer:
(d) Bitwise operations

Question 23.
The average humanear can detect __________ Hz sound waves.
a) between 20 and 20,000 Hz
b) upto 10000 Hz
c) Less than 5000
d) None of these
Answer:
a) between 20 and 20,000 Hz

Question 24.
The amount of RAM that can be accessed by a microprocessor at one time is determined by ……………….
(a) clock speed
(b) word size
(c) instruction
(d) software
Answer:
(b) word size

Question 25.
Sound waves above 5,000 Hz have a high pitch and are called “treble” frequencies.
a) treble
b) bass
c) Either A or B
d) None of these
Answer:
a) treble

Question 26.
What will be the value of of control line for read operation from RAM to MDR?
(a) 1
(b) 0
(c) 1
(d) 2
Answer:
(a) 1

Question 27.
Each CPU is rated at a specific __________ speed.
a) clock
b) bus
c) cable
d) wave
Answer:
a) clock

Question 28.
Which of the following digital circuit is used to point to the specific memory location where the word can be located?
(a) Logic gate
(b) Transistor
(c) Encoder
(d) Decoder
Answer:
(d) Decoder

Question 29.
The modern processors can perform __________ instructions per second.
a) million
b) billions
c) Either A or B
d) None of these
Answer:
c) Either A or B

Question 30.
Which one of the following is not a RISC processor?
(a) Pentium IV
(b) AMD K6
(c) Intel P6
(d) AMD K8
Answer:
(d) AMD K8

Question 31.
Every microprocessor has a(n) __________ that regulates the speed at which it executes instructions.
a) internal clock
b) control bus
c) speed bus
d) None of these
Answer:
a) internal clock

Question 32.
Which of the following memory is of higher cost?
(a) Hard disk
(b) Main memory
(c) Cache memory
(d) Floppy
Answer:
(c) Cache memory

Question 33.
A command which is given to a computer to perform an operation on data is called an __________
a) code
b) program
c) instruction
d) None of these
Answer:
c) instruction

Question 34.
In which of the following memory, contents can be erased by exposing to ultraviolet rays?
(a) ROM
(b) EPROM
(c) PROM
(d) RAM
Answer:
(b) EPROM

Question 35.
The instruction set carries out the __________ operations.
a) Data transfer and Arithmetic operations
b) Logical operations and Control flow
c) Input/output
d) All the above
Answer:
d) All the above

Question 36.
The time taken to respond to a read/write operation is ………………….
(a) response time
(b) access time
(c) both (a) and (b)
(d) sequential time
Answer:
(c) both (a) and (b)

Question 37.
__________determines the amount of RAM that can be accessed by a microprocessor.
a) word size
b) clock speed
c) program execution
d) None of these
Answer:
a) word size

Question 38.
Which one of the following has the stacked arrangement of disks?
(a) CD
(b) DVD
(c) Blu – Ray
(d) Hard disk
Answer:
(d) Hard disk

Question 39.
The first commercial microprocessor is __________.
a) Intel 3004
b) Intel 4044
c) Intel 4004
d) All the above
Answer:
c) Intel 4004

Question 40.
What is the colour of the double-layered sides DVD?
(a) Silver
(b) Green
(c) Gold
(d) Brown
Answer:
(c) Gold

Question 41.
In a microprocessor, the number of output pins is always equal to the number of __________
pins.
a) input
b) result
c) memory
d) None of these
Answer:
a) input

Question 42.
DVD uses a …………………. colour laser to read and write data.
(a) red
(b) green
(c) blue
(d) orange
Answer:
(a) red

Question 43.
A microprocessor which consists of 4 input pins and 4 output pins are called __________ bit microprocessor.
a) 32
b) 16
c) 8
d) 4
Answer:
d) 4

Question 44.
USB 3.0 can transfer data up to ………………….
(a) 3 GB/sec
(b) 5GB/sec
(c) 5GB/min
(d) 3GB/min
Answer:
(b) 5GB/sec

Question 45.
Match the following.
Samacheer Kalvi 11th Computer Science
(a) (1) (2) (3) (4)
(b) (4) (3) (2) (1)
(c) (2) (3) (4) (1)
(d) (3)(4) (2) (1)
Answer:
(c) (2) (3) (4) (1)

Question 46.
Currently most of the microprocessors use __________bit architecture.
a) 32
b) 64
c) 32 bit or 64
d) 32 bit or 16
Answer:
c) 32 bit or 64

Question 47.
The areas between the pits in CD’s are called ………………….
(a) memory
(b) bus
(c) buffer
(d) lands
Answer:
(d) lands

Question 48.
MDR stands for __________
a) Memory Data Register
b) Memory Data Record
c) Memory Data Regulator
d) Memory Design Register
Answer:
a) Memory Data Register

Question 49.
How are sound waves close to 20 Hz with low pitch called?
(a) Treble
(b) Tremble
(c) Bass
(d) Accumulator
Answer:
(c) Bass

Question 50.
The __________ keeps the data which is transferred between the memory and the CPU.
a) Memory Data Register
b) Memory Address Register
c) Both A and B
d) None of these
Answer:
a) Memory Data Register

PART – 2
II. Short Answers

Question 1.
Write a note on computer organization.
Answer:
Computer organization deals with the hardware components of a computer system. It is concerned with how the various components of computer hardware operate.

Question 2.
What are the components of CPU?
Answer:
The CPU has a Memory Data Register (MDR) and a Memory Address Register (MAR). The MDR keeps the data which is to be transferred between memory and the CPU. The ALU of CPU places the address of the memory to be fetched into MAR.

Question 3.
What is Microprocessor?
Answer:
The microprocessor is a programmable multipurpose silicon chip. It is driven by clock pulses. It accepts input as binary data and after processing, it provides the output data as per the instructions stored in the memory.

Question 4.
Define a BUS?
Answer:

  1. A bus is a collection of wires used for communication between the internal components of a computer.
  2. The three types of buses are: address bus, data bus and control bus.

Question 5.
What is a “treble”?
Answer:
Sound waves above 5,000 Hz have a high pitch and are called “treble” frequencies.

Question 6.
What is meant by Hard Disk?
Answer:

  1. Hard disk is a magnetic disk on which user can store data.
  2. The hard disks has the stacked arrangement of disks accessed by a pair of heads for each of the disk.
  3. The hard disks come with a single or double-sided disk.

Question 7.
What is the use of an internal clock?
Answer:
Every microprocessor has an internal clock that regulates the speed at which it executes instructions.

Question 8.
Why the Blu – Ray disc is called so?
Answer:
Since it uses a blue-violet laser to write, hence it is called so.

Question 9.
What is an instruction?
Answer:
A command which is given to a computer to perform an operation on data is called an instruction.

Question 10.
Expand RISC, CISC
Answer:
RISC stands for Reduced Instruction Set Computers CISC stands for Complex Instruction Set Computers.

Question 11.
What are the various operations carried out by the instruction set?
Answer:
The instruction set carries out the following types of operations:

  • Data transfer
  • Arithmetic operations
  • Logical operations
  • Control flow
  • Input/output

Question 12.
Expand HDMI
Answer:
HDMI – High Definition Multimedia Interface

Question 13.
Write a note on the first commercial microprocessor.
Answer:
The first commercial microprocessor, Intel 4004 is a 4-bit processor. It has 4 input pins and 4 output pins. It can process 4 bits at a time. So it is called a 4-bit processor.

Question 14.
Name the types of operations performed by the Instruction Set.
Answer:

  1. Data transfer
  2. Arithmetic operations
  3. Logical operations
  4. Control flow
  5. Input/output

Question 15.
Write a note on the program counter.
Answer:
The Program Counter (PC) is a special register in the CPU which always keeps the address of the next instruction to be executed.

Question 16.
What is RISC?
Answer:
RISC stands for Reduced Instruction Set Computers. They have small set of highly optimised instructions. Example Pentium IV, intel P6, AMD K6 and K7.

Question 17.
What is the function of the address bus?
Answer:
The address bus is used to point to a memory location. The address bus is unidirectional.

Question 18.
What are the two types of accessing methods to access the memory?
Answer:
The two types of accessing methods are:

  1. In sequential access, the memory is accessed in an orderly manner from starting to end.
  2. In random access, any byte of memory can be accessed directly without navigating through previous bytes.

Question 19.
Give the Block diagram of microprocessor-based system.
Answer:
Class 11 Computer Science Chapter 3 Notes Samacheer Kalvi

Question 20.
What are the functions of a control bus?
Answer:
The control bus controls both read and write operations. The read operation fetches data from memory and transfers it to MDR. The write operation transfers data from the MDR to memory.

PART – 3
III. Explain in Brief

Question 1.
Explain Microprocessor units.
Answer:
The microprocessor is made up of 3 main units.
They are:

  • Arithmetic and Logic Unit (ALU): To perform arithmetic and logical instructions based on computer instructions.
  • Control unit: To control the overall operations of the computer through signals.
  • Registers (Internal Memory): They are L used to hold the instruction and data for the execution of the processor.

Question 2.
What is RAM?
Answer:
The main memory is otherwise called as Random Access Memory. This is available in computers in the form of Integrated Circuits (ICs). It is the place in a computer where the Operating System, Application Programs and the data in current use are kept temporarily so that they can be accessed by the computer’s processor.

Question 3.
What is ALU?
Answer:
Arithmetic and Logic Unit (ALU):
To perform arithmetic and logical instructions based on computer instructions.

Question 4.
What are the memory access methods?
Answer:
The memory access methods are

  • Sequential Access: The memory is accessed in an orderly manner from start to end.
  • Random Access: Any byte of memory can be accessed directly without navigating through previous bytes.

Question 5.
What is a microprocessor?
Answer:
The microprocessor is a programmable multipurpose silicon chip. It is driven by clock pulses. It accepts input as binary data and after processing, it provides the output data as per the instructions stored in the memory.

PART – 4
IV. Explain in Detail

Question 1.
Explain CD-ROM and DVD-ROM.
Answer:
CD-ROM :
A CD or CD-ROM is made from 1.2 millimeters thick, polycarbonate plastic material. A thin layer of aluminum or gold is applied to the surface. CD data is represented as tiny indentations known as “pits”, encoded in a spiral track moulded into the top of the polycarbonate layer. The areas between pits are known as “lands”. A motor within the CD player rotates the disk. The capacity of an ordinary CD- ROM is 700MB.

DVD-ROM :
A DVD (Digital Versatile Disc or Digital Video Disc) is an optical disc capable of storing up to 4.7 GB of data, more than six times what a CD can hold. DVDs are often used to store movies at a better quality. Like CDs, DVDs are read with a laser.

The disc can have one or two sides, and one or two layers of data per side; the number of sides and layers determines how much it can hold. A 12 cm diameter disc with a single-sided, single layer has 4.7 GB capacity, whereas the single sided, the double layer has 8.5 GB capacity. The 8 cm DVD has a 1.5 GB capacity.

The capacity of a DVD-ROM can be visually determined by noting the number of data sides of the disc. Double-layered sides are usually gold-colored, while single-layered sides are usually silver-colored, like a CD.

Question 2.
Explain the flash memory devices and Blu-ray disc.
Answer:
Flash Memory Devices:
Flash memory is an electronic (solid-state) non – volatile computer storage medium that can be electrically erased and reprogrammed. They are either EEPROM or EPROM. Examples of Flash memories are pen drives, memory cards, etc. Flash memories can be used in personal computers, Personal Digital Assistants (PDA), digital audio players, digital cameras, and mobile phones. Flash memory offers fast access times. The time taken to read or write a character in memory is called access time. The capacity of the flash memories varies from 1 Gigabyte (GB) to 2 Terabytes (TB).

Blu – Ray Disc:
Blu – Ray Disc is a high – density optical disc similar to DVD. Blu-ray is the type of disc used for PlayStation games and for playing High – Definition (HD) movies. A double – layer Blu – Ray disc can store up to 50 GB (gigabytes) of data. This is more than 5 times the capacity of a DVD, and above 70 times of a CD. The format was developed to enable recording, rewriting and playback of high – definition video, as well as storing large amount of data. DVD uses a red laser to read and write data. But, Blu – ray uses a blue-violet laser to write. Hence, it is called as Blu – Ray.

Question 3.
Explain briefly about the Blu-Ray disc.
Answer:
Blu-Ray Disc is a high-density optical disc similar to DVD. Blu-ray is the type of disc used for PlayStation games and for playing High-Definition (HD) movies. A double-layer Blu-ray disc can store up to 50GB (gigabytes) of data. This is more than 5 times the capacity of a DVD, and above 70 times of a CD.

The format was developed to enable recording, rewriting, and playback of high-definition video, as well as storing a large amount of data. DVD uses a red laser to read and write data. But, Blu-ray uses a blue-violet laser to write. Hence, it is called as Blu-Ray.

Question 4.
Explain the secondary storage devices.
Answer:
Secondary Storage Devices:
A computer generally has limited amount of main memory which is expensive and volatile. To store data and programs permanently, secondary storage devices are used. Secondary storage devices serve as a supportive storage to main memory and they are non – volatile in nature, secondary storage is also called as Backup storage

Hard Disks:
The hard disk is a magnetic disk on which you can store data. The hard disk has the stacked arrangement of disks accessed by a pair of heads for each of the disks. The hard disks come with a single or double-sided disk.

Compact Disc (CD):
A CD or CD – ROM is made from 1.2 millimeters thick, polycarbonate plastic material. A thin layer of aluminum or gold is applied to the surface. CD data is represented as tiny indentations known as “pits”, encoded in a spiral track moulded into the top of the polycarbonate layer. The areas between pits are known as “lands”. A motor within the CD player rotates the disk. The capacity of an ordinary CD – ROM is 700 MB.
Computer Organization Class 11 Samacheer Kalvi

Digital Versatile Disc (DVD)
A DVD (Digital Versatile Disc or Digital Video Disc) is an optical disc capable of storing up to 4.7 GB of data, more than six times what a CD can hold. DVDs are often used to store movies at a better quality. Like CDs, DVDs are read with a laser.
The disc can have one or two sides, and one or two layers of data per side; the number of sides and layers determines how much it can hold. A 12 cm diameter disc with a single-sided, the single-layer has 4.7 GB capacity, whereas the single-sided, double-layer has 8.5 GB capacity. The 8 cm DVD has a 1.5 GB capacity. The capacity of a DVD-ROM can be visually determined by noting the number of data sides of the disc. Double – layered sides are usually gold – coloured, while single-layered sides are usually silver – coloured, like a CD.
Samacheer Kalvi 11th Computer Science Guide

Fash Memory Devices:
Flash memory is an electronic (solid-state) non – volatile computer storage medium that can be electrically erased and reprogrammed. They are either EEPROM or EPROM. Examples for Flash memories are pen drives, memory cards etc. Flash memories can be used in personal computers, Personal Digital Assistants (PDA), digital audio players, digital cameras, and mobile phones. Flash memory offers fast access times. The time taken to read or write a character in memory is called access time. The capacity of the flash memories varies from 1 Gigabyte (GB) to 2 Terabytes (TB).

Blu-Ray Disc:
Blu-Ray Disc is a high-density optical disc similar to DVD. Blu-ray is the type of disc used for PlayStation games and for playing High-Definition (HD) movies. A double – layer Blu-Ray disc can store up to 50GB (gigabytes) of data. This is more than 5 times the capacity of a DVD, and above 70 times of a CD. The format was developed to enable recording, rewriting, and playback of high-definition video, as well as storing a large amount of data. DVD uses a red laser to read and write data. But, Blu-ray uses a blue-violet laser to write. Hence, it is called as Blu-Ray.

Question 5.
Explain the cache memory.
Answer:
Cache Memory:
The cache memory is a very high-speed and expensive memory, which is used to speed up the memory retrieval process. Due to its higher cost, the CPU comes with a smaller size of cache memory compared with the size of the main memory. Without cache memory, every time the CPU requests the data, it has to be fetched from the main memory which will consume more time. The idea of introducing a cache is that, this extremely fast memory would store data that is frequently accessed and if possible, the data that is closer to it. This helps to achieve the fast response time, Where response time, (Access Time) refers to how quickly the memory can respond to a read / write request. Arrangement of cache memory between the CPU and the main memory is shown below
11th Samacheer Computer Science Book Back Answers

Question 6.
Explain main memory and its types.
Answer:
The main memory is otherwise called Random Access Memory. This is available in computers in the form of Integrated Circuits (ICs). It is the place in a computer where the Operating System, Application Programs and the data in current use are kept temporarily so that they can be accessed by the computer’s processor. The smallest unit of information that can be stored in the memory is called a bit. The memory can be accessed by a collection of 8 bits which is called a byte. The bytes are referred by ‘B\ If a computer has 1 megabyte of memory, then it can store 10,48,576 bytes (or characters) of information. [Hence 1MB is 1024KB and 1 KB is 1024 Bytes, So 1024 X 1024 =10,48.576 Bytes].

Types of RAM:
There are two basic types of”RAM

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

These two types differ in the technology they use to hold data. Dynamic RAM being a common type needs to be refreshed frequently. Static RAM needs to be refreshed less often, which makes it .faster. Hence, Static RAM is more expensive than Dynamic RAM.