Computer Science (Ist Semester) Chapter # 01 & 02
Introduction to Computer
Q:1 Describe the history and development of computer?
Ans:-Man is always finding ways to ease his physical and mental labour.
To ease his physical and mental labour he develop different machines
and devices. Early machines could simply add, subtract, multiply and divide
the numbers. Modern computer have grown up as the fastest and powerful
tools as a result of technological innovations during last 50 years.
Rapid progress in electronics had made it possible to bring the Computer
with in the reach of everyone. Modern Computer has enable man to
conquer space and is helping Man in every sphere of life.
The present age is the information age. Whether you are a teacher or a
student, a doctor or a patient, a pilot or an engineer, a scholar or a
businessman, the information Super High Way (computer) fulfills the need
of everyone.
Q2.What is the name of the earliest device that helps the user in
calculation and still is in use? Describe its structure and working.
Ans:- Name of that device is Abacus. It is very oldest and simplest
computing device. It is was developed around 3000 B.C.
Structure and Working:
1-It consists of a wooden rectangular frame.
2-The frame has a number of parallel wires.
3-Each wire has several beads.
4-These beads can freely slide on these parallel wires.
5-Each bead in the Abacus represents a digit.
Usage: 1-It was used in counting and to memorize the different accounts.
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Q3.A man discover a new idea to multiply and divide
numbers using a set of ivory rods. Explain that idea?
Ans:- Napier discovered that it is possible to multiply and divide number by
simple adding and subtracting their representation in geometrical series called
"logarithm" .Napier placed the top logarithm of number on a set of ivory rods. These
rods were known as Napier's bones. The product of two numbers was obtained
mechanically by positioning those Napier's bones.
Q4.The idea of the logarithm gave birth to a calculating device.
What is the name of that device and how many parts it has?
Ans:- The name of that device is Slide Rules.
Its parts.
A-Slide Rules consists of two scales:
(1)The rule (2)The slide
Slide rule also has a transparent rectangular moving piece called cursor.
The cursor is capable to slide smoothly over slide rule.
It was used to multiply ,taking power and root of the number.
Q5.Write a note on Blaise Pascal calculator.
Ans:- Pascal line:
After the idea of Napier bones and slide rule, Blaise Pascal developed a machine in
1642. The name of his machine is Pascal Line.
It can only add and subtract. It consists of series of wheels or dial .Each dial has 10
digits from 0 to 9.These dials were geared with drums. Drums also have digits 0 to 9 3
which were displayed through windows.
Q6.Who develop difference Engine and who discarded this idea?
Ans:- Difference Engine:
In 1786 J.H Muller gave the idea of a calculating machine. Charles Babbage worked on
that idea and developed a machine in 1812. It was called Difference Engine. After 19
years of labour, Charles Babbage stopped working on Difference Engine. He began to
work on a new machine called “Analytical Engine”.
Q7.Babbage designed a general purpose machine that includes
many features of today’s computer. Give the details of that
machine?
Ans:- Analytical Engine:
Babbage gave up the idea of difference engine and began to work on a new machine
called Analytical engine. Analytical engine could be programmed to evaluate a wide
range of arithmetical expressions. The machine was fully automatic. Babbage’s
Analytical engine had several features of today’s digital computer. Babbage’s Analytical
engine could not be completed due to under developed technology of his time but he
laid the foundation stone for the development of modern digital computer. That is why
he is also called the father of modern digital computer. 4
Details:Analytical engine consists of five units:
(1)Store :This part was to store the number entered in to machine and those
which were generated at the time of processing.
(2)Mill :This was the processing unit that had to perform all the Arithmetic
operation automatically by rotation of gears and wheels.
(3)Control :Control unit had to control the other unit .Moreover it had to
transfer the number and instructions from the store to the mill and vice
versa. It worked with the rotations of gears and wheels.
(4)Input :This Unit entered the data and instructions into the store .The input
media had to be in the form of punched cards.
(5)Output :The output unit displayed the results of calculations.
Q8.Write a note on mark-1.(The computer that used relays,
weighted tones and binary number system and known as a
complex calculator)Write the name of that machine and who
developed it?
Ans:- Important features of mark-1
Automatic Sequence Controlled Calculator (ASCC) or mark-1 was designed by Dr.
Howard Aiken in 1944.This type of mechanical calculators were heavy, large and
slow.Mark-1 was 15.5 meters long and weighed 5 tons.It used 3300 electromagnetic
relays.This machine remained in operation till 1959.It was first machine that used
binary system.
Q9.Electronic computer history based on different generations
and having various kinds of impacts. Discuss the generations. of
electronic computer?
Ans:- Electronic Computer:
1-The invention of vacuum tube in 1905 opened the gates for the developed of
electronic computer.
2-Vacuum tubes were used as electronic switches instead of relays in earlier electronic
computer.
3-Vacuum tubes were noise less and could work at a fantastic speed as compared to
relays.
Generations of Computer:
The development of electronic computer can be divide into five generations depending 5
upon technologies used in it. The generations of computer are :
1-First generation (Invention of vacuum tube in 1906) 1942 ------1959
2-Second generation (Transistor in1947) 1959-------1965
3-Third generation (integrated circuits IC’s in1965) 1965--------1973
4-Fourth generation (Microprocessor,1974) Since 1972
5-Fifth generation (Artificial intelligence) in progress since 1980
Q10.Write a note on First Generation Computers.
Ans:- First Generation Computers:
1: ENIAC (Electronic Numerical Integrator and Calculator):
It was built at university of Pennsylvania. It contained nearly 18,000 tubes and6
consumed 150 KW of power. ENIAC was very big and weighed more than 30 tons. It
could perform 5000 additions and hundreds of multiplications per second.
2: EDSAC (Electronic Delayed Storage Automatic Computer):
It was developed in 1949.It was the first computer that used stored programs.
3: EDVAC (Electronic Discrete Variable Automatic Computer):
The program and data fed in EDVAC through punched paper tapes.
4: UNIVAC-1 (Universal Automatic Computer):
It was the first commercially successful machine. It was made in 1951. It was an
automatic computer and could work 24 hours a day.ENIVAC-1 used magnetic tapes as
input media.
Defects of first Generation Computers:
The first generation computer had following short comings:
1: Very big in size 2: Slow in speed 3: Low reliability 4: Large power
consumption
Q11.Write a note on Second Generation Computers .
Ans:- Second Generation Computers: Transistors was invented in 1948.
As compared to vacuum tubes, transistors are smaller, more reliable and consume less
power. Second Generation computers were developed using transistors that were able
to perform a single operation in micro seconds and were capable to store huge data as
card readers, magnetic tapes, magnetic disks. etc. These machines used computers
simple languages similar to English for computer programming.
Q12.Write a note on third Generation Computers .
Ans:- Third Generation Computers:
In the sixties (1960s) the integrated circuit (ICs) appeared with the development of
microelectronics technology. An IC chip contain many components (such as transistors,
diodes and resistances) inter connected with each other.
Third generation computer have small size and consumed very little power but their
speed and storage capacity had largely been increased using integrated circuit .For
example: IBM computer model 85 of its system 360 series is an example of third
generation computer
Q13.Write a note on fourth Generation Computers .
Ans:- Fourth Generation Computer:
Very-large-scale integration VLSI was developed in 1971. A VLSI
contained a complete central processing unit CPU on a single Silicon Chip.
The first microprocessor (µP) Intel 4004 was a 4-bit µP capable of performing
arithmetical logical and control functions. Intel developed an 8-bit µP in 1973.
The use of microprocessors produced cheap computers called Micro computer or
Personal computers. Apple series designed in 1976 using 8-bit µP. Commodore and
PET are also popular personal computer. In 1978 the evolution of 16-bit µP greatly 7
increased processing components speed of the computer.
Q14.Write a note on fifth Generation Computers.
Ans:- Fifth Generation Computer:
Fourth generation computer are of very high speed and have a lot of capacity to store
data. However lack of thinking power in computer was a challenge for the scientists.
The fifth generation computer are a step in this direction These will be capable of:
i)Reasoning ii)Drawing results iii)Making decision
VLSI technology has made it possible to put millions of components on a
semiconductor chip. Improvement in hardware and software may produce very
powerful computers than those current in use. Artificial intelligence and expert systems
will been important part of these newer fifth generation computers.
Q15.What is a Hybrid Computer?
(The combination of the best features of analog and digital computers produced
fast and accurate computers.)
(A)What is Name Hybrid computer. B)Write
down the main application of Hybrid computers.
Ans:- A hybrid computer combines the best features of analog and digital computers.
Hybrid computers are special purpose computers which are fast and accurate. Hybrid
computers help the user to handle both the analog and digital data. Hybrid computers
are generally used in telemetry (measure scientific data over long distances),
spaceships, guided missiles, industrial processing and hospitals etc.
Q16.What is difference between Analog and Digital Computer?
Ans:Analog Computer Digital Computer
1 Analog computer accept the data in
physical or continuous form.
1 Digital computers accept the data in the
form of digits.
2 Analog computers measure the physical
quantities.
2 In Digital Computers the quantities are
counted, rather than measured.
3 Analog computers represent the data in
a suitable form by an indicator.
3 In Digital Computers data is represented
in the form of visual effects on a screen.
4 Analog computers perform scientific
operations.
4 Digital Computers are used for Scientific
and business purpose.
5 Analog computers are very fast in
processing.
5 Modern Digital Computers are capable to
do computations at a very high speed.
6 Analog computers are not very accurate. 6 Digital Computers are very accurate.
7 Analog computers can be used in
industrial units to control various
machines.
7 Digital Computers are used in banks,
offices, companies, schools etc.
8 Analog computers are special purpose
computers.
8 Digital Computers are general purpose
computers.
9 Analog computers accept the data i.e
speed, distance, time, temperature etc
9 Digital Computers process numbers
using arithmetical and logical operations.
Q17.How computers are classified according to their size, speed
and power of processing?
Ans:- Computers are classified as:
a)Super-Computer
b)Mainframe computer
b)Mini-Computer
d)Micro-Computer
Q18.Write a note on Super-computer.8
Ans:- Super-computer: Supercomputers are the largest in size, having the
fastest speed and most expensive computers developed in 1980s to handle
complicated problems and scientific operations. These computers are used in large
organizations, in scientific laboratories, in aerospace industries, in research centers and
for weather forecasting etc.
Q19.Write a note on Mainframe-computer.
Ans:- Mainframe-computer :Mainframe computers are larger than mini
computers in size, costly, fast processing speed and power. These computers have the
facilities to handle large amount of data and support several input/output devices. A
Mainframe computer together with its supporting equipments costs about millions of
dollars. These computers are used in large business corporations, research
laboratories, passport office, airports for immigration records, travel agencies for
reservations etc.
Examples: CYBER 176.IBM 4341 etc.
Q20.Write a note on Minicomputers.
Ans:- Minicomputers: Digital Equipment Corporation introduced minicomputers.
They are small in size, speed, storage and other capabilities. Minicomputers are low
cost computers. Integrated circuits are used in them. Microcomputers can support
multiple-user and multiple tasks like main frame computers through the use of
terminals.
Minicomputers are used In business organizations, in universities and colleges, in
government organizations and in engineering.
Q21.Write a note on Microcomputer.
Ans:- Microcomputer: Microcomputer was introduced in early 1970s after the
invention of microprocessor. Today’s microcomputer is the equivalent of yesterday’s
minicomputers. A microcomputer is also known as personal computer (PC).A
microprocessor is a semiconductor large scale integrated (LSI) or Very-large-scale
integration (VLSI) circuit having processing capabilities. These computers are used in
scientific and research laboratories, in bank, companies and offices, for Education in
schools, Colleges, Universities etc.
Examples: IBM-PC, AT&T, PS/2, Pentium 1-1V and Apple Macintosh etc.
Q-22.What is the impact of computer on society?
Ans:- As computers have acquired more features, they have acquired more use as
well. They can be used as typewriters, calculators, accounting systems, record keepers
and telecommunication instruments. They can also act as tutors and toys.
Microcomputers have wide variety of uses in homes. Even people with little or no
programming experience can use microcomputers. With each passing day, computers
are more and more involved in our lives and are affecting us in many ways. In banks,
factories, stores, schools, offices or even in homes we find computers or computerized
systems all around us. We are using computerized microwave ovens, washing
machines, VCRs etc. We are also using computerize bank transactions, computerized
shopping etc. Computer makes us more productive in many of our jobs. In hospitals we
have better diagnosis, proper treatment and better healthcare. Thus computer have
changed the way we work, the way we learn and the way we communicate. It is helping
us to do thing efficiently and accurately.
Q-23 What is the impact of internet on society?
Ans:- Internet is the system of worldwide computer networks that enables the 9
internet users to exchange information with each other. Computers can be hooked
to telephones through modems so that data can be sent and received over
telephone lines. Telecommunication provides several new ways to communicate via
computers.
Today internet is a global web of nearly 1 million computer networks, at least 50
millions computers and 200 million people around the world. Internet hosts are
connected to the internet round the clock. Thousands more join this global network
each month. Internet provides many services to million of people. Through internet
you can get access of thousands of databases and talk with expertise worldwide on
any subject. You can find jobs, get solution of your technical problems, sell products
and conduct researches. Internet has now become the need of us because of the
vast array (Way of storing data) of information and activities which are possible with
it.
Q-24 Which are the different applications of computer in
different field of life?
Ans:- Computer applications are being used as under:1-Applications in business
2- applications in Banking
3- applications in Stock exchange
4- applications in Retailing
5-Application in education:
6-Applications in medical field
7-Applications in science
8- Applications in Product design and manufacturing
Q-25 How computer applications are used in business?
Ans:- Applications in business: Computers are used to keep record of
stocks of raw materials as well as finished products, making customer’s bill,
analyzing sales of various products hundreds of other functions related to accounts,
stocks, employees, customers, importers, exporters, banks, stock exchanges,
income tax etc.
Q-26 How computer applications are used in Banking?
Ans:- Banking applications: Banks are the largest users of computers.
Computers are used for day-to-day processing of customers’ accounts and payments
of cheques, drafts etc. Computers inform when an installment of loan will be due. Now
a day customers can make purchases at stores using credit cards.
Q-27 How computer applications are used in Stock exchange?
Ans:- Stock exchange applications: Rapidly growing volume of the stock
markets has proportionally increased the paperwork problems. Traders had to wait to
allow stock market brokers to update before they may open business the following day.
Computers can perform jobs efficiently with greater accuracy than it was done manually
in the past.
Q-28 How computer applications are used in Retailing sector?
Ans:- Retailing applications: In the commercial sector computers are used to
write sale reports, financial statements, products cost, volume and profile analysis, 10
keep record of stolen, lost and damage items. The black and white bar-code printed
on most of the products in supermarkets is called Universal Product Code (UPC). UPC
is the key to computer controlled supermarket check-out. It is also updating the store’s
inventory list, warning the manager about an item going to be short. The information so
obtained can also be used by marketing experts.
Q-29 How computer applications are used in education?
Ans:- Application in education: There are number of methods in which
educational institutions can use computers to educate the students.
a Computer Assisted Instructions (CAI): It does not involve teaching
about computers but rather using computers as an aid in teaching a subject.
There are four major types of CAI system: 1- Drill and practice. 2-Tutorial. 3Testing 4-Dialogue
b Computer Managed Instructions (CMI): In a computer-managed
instruction (CMI) system, instead of teaching the students directly, the computer
assigns a student to read certain book, listen certain tape and attend certain
lecture and so on. On completing the assignments, the student returns to the
computer for testing and further assignment.
c Computer-Based Simulations: Simulation is used when direct
experimentation is impossible or economical unbearable.
Q-30 How computer applications are used in medical field?
Ans:- Applications in medical field: Computer is used for basic tasks
such as keeping track of patient’s appointments, diagnosis and treatment
procedures. The computer acts as sort of medical consultant who can help a
doctor to diagnosis a disease and to prescribe best suitable treatment. The
largest use of computers is in the hospital administration. It is also used for
patient’s health care and medical researches.
Q-31 How computer applications are used in Science?
Ans:- Applications in Science: There are a lot of Computer
applications in the field of science and researches such as in Physics, Chemistry,
Mathematics, Biological Science, Medical Science, Agricultural Science,
Computer Science itself, and Nuclear Physics etc. It is impossible to carry out
scientific researches without computers.
Q-32 How computer applications are used in Product design
and manufacturing?
Ans:- Product design and manufacturing: Computer-aided design
software (CAD) provides us ways to develop a presentation of the product and to
test it in a variety of simulated environments. Auto CAD provides us facility to
see the house before building it up.
11
Q33-What is a Programming language?
Ans:- To perform a job, a computer needs instructions from the users. The
instructions given to a computer to perform certain task is called a program. In other
words programming is a way to communicate with computer. An electronic digital
computer uses binary number system having digits 1 to 0 to understand the given
instructions. These 0’s or 1’s represent On or Off state of certain electronic switch
code or machine language that would cause the computer to perform certain
operation. These are easy to understand Programming languages can be classified
as:
1-Machine Language 2-Assembly language 3-Symbolic language.
Q34-What is a difference between machine languages and
assembly languages?
Ans:- Machine Languages (Low level language): The set of binary
instruction codes ( Machine language) is the most fundamental language of the
computer. It is also called the low level language. Data and instructions are first
converted in the machine language before it is sent to the computer so that
computer can understand and respond accordingly.It is different for different
computers.
Assembly Languages (Low level language): Assembly language unlike
machine language consists of short symbolic phrases, alphanumeric symbols called
mnemonics (special word for remembering) because it is very close to the machine code
of a computer. Assembly language is different for different computers. A programme
written in Assembly Language must go to an Assembler. Assembler is system software
which translates Assembly Language into Machine Language. Assembly languages
have the following advantages over machine languages: 1-Easier to understand 2Easier to locate errors and correct 3-Easy to modify.
Q35- Why high level languages are more beneficial than low level
languages?(Write a note on High level Languages)
Ans:- Symbolic Languages ( High level Languages ): The difficulty
in understanding the machine language by the user was resolved by symbolic
coding using simple English-like words which a user can understand more easily.
The programs written in these languages are then translated into machine language.
The idea became the base for the development of a large number of different
symbolic programming languages which are easy to use and understand. These
languages are more suitable than machine languages for human use and enable the
programmer to write instructions easily. These symbolic languages are called high
level languages. High level Languages are Basic, FORTRAN, COBOL, Pascal, Ada,
C, C++ and Java.
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Q36- Write a note on the following languages.
Basic,Fortran, COBOL,PASCAL,ADA,C and C++
Ans:- Basic: ( Beginner’s All-purpose Symbolic Instruction Code)Basic was
developed in 1964. It is sufficiently close to English and is one of the most widely used
and easy-to-learn high level language.
Fortran (FORmula TRANslation) :Fortran was developed in 1975 for IBM computers.
It was designed to solve mathematical, scientific and engineering problems.
COBOL (Common Business Oriented Languages): COBOL was developed in 1959.
COBOL was the first high level computer language suitable fro handing large amount of
data related to pay roll, credit and debit accounts, inventory and variety of other
business applications.
PASCAL: PASCAL is a programming language named after the French
mathematician and scientist Blaise Pascal.
ADA: ADA is a programming language for real time developed in 1980 for use in
military applications. It is named after one of the first programming Augusta Ada Byron.
C :is the full name of programming language developed in 1974 by Brian
Kernighan and Dennis Ritchie.
C++ : C++ was developed by Bjarne Stroustrup in the early 1980s.Like C, C++ is an
extremely powerful and efficient language. But C++ is even more difficult to learn than
C.
Q37- Into how many generations the computer languages are divided.?
Ans:- Generation of computer languages: Machine languages are first
generation languages and Assembly languages are considered second generation
languages. Third Generation Languages are portable unlike assembly Languages.
Third Generation Languages can be designed to run on multiple PCUs. For
Example.FOTRAN,COBOL,PASCAL,BASIC,C,C++ etc
Fourth generation languages ( 4GLs) are mostly special purpose programming
languages that are easier to use than third generation languages.
Some Fourth Generation Languages ( 4GLs) are:
a) VISUAL BASIC :One of the 4GL which is not a special purpose language
is Visual-Basic. Visual Basic supports object-oriented features and methods.
b) JAVA: Java is an object-oriented programming language developed in
1991. It was originally developed for use in set-top boxes, transitioned to the
world wide Web in 1994.
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13
Q 38-What is a compiler? How does it differ from an Interpreter?
Ans:- A language processor is a “translating-software”. That enables a computer to
respond the user’s instructions by converting user’s instructions into machine code.
There are two types of language processors.
1- Compilers
2- Interpreters
1-COMPILERS. A compiler automatically converts a programme written in some high
level language into an Equivalent Low Level Machine Language so that computer can
understand and respond properly. A compiler can translate only that source
programme that has been written in a language for which it is designed.
2-INTERPRETER. An interpreter translates the statements written in High Level
Language into an equivalent Low Level machine Language one by one and Executes it
before translating the next statement of the source programme. Interpreter do not
require large computer memory, however, it is time consuming.
Q: 39 Define the following.
1- Source Program
2- Object Program
Ans:- 1-SOURCE PROGRAM:A program written by a programmer in a language other
than machine language is called a source program.
2-OBJECT PROGRAM: The output from a compiler which consists a machine language
instructions is called an Object Program.
All questions for self Test
Computer Science (Ist Semester) Chapter # 01
All questions for self Test
Q:1 Describe the history and development of computer?
Q2.What is the name of the earliest device that helps the user in calculation and still is in use?
Describe its structure and working.
Q3.A man discover a new idea to multiply and divide numbers using a set of ivory rods.
Explain that idea?
Q4.The idea of the logarithm gave birth to a calculating device. What is the name of that
device and how many parts it has?
Q5.Write a note on Blaise Pascal calculator.
Q6.Who develop difference Engine and who discarded this idea?
Q7.Babbage designed a general purpose machine that includes many features of today’s
computer. Give the details of that machine?
Q8.Write a note on mark-1.(The computer that used relays, weighted tones and binary number
system and known as a complex calculator)Write the name of that machine and who
developed it?
Q9.Electronic computer history based on different generations and having various kinds of
impacts. Discuss the generations. of electronic computer? 14
Q10.Write a note on First Generation Computers.
Q11.Write a note on Second Generation Computers .
Q12.Write a note on third Generation Computers .
Q13.Write a note on fourth Generation Computers .
Q14.Write a note on fifth Generation Computers.
Q15.What is a Hybrid Computer?
Q16.What is difference between Analog and Digital Computer ?
Q17.How computers are classified according to their size, speed and power of processing?
Q18.Write a note on Super-computer.
Q19.Write a note on Mainframe-computer.
Q20.Write a note on Minicomputers.
Q21.Write a note on Microcomputer.
Q-22.What is the impact of computer on society?
Q-23 What is the impact of internet on society?
Q-24 Which are the different applications of computer in different field of life?
Q-25 How computer applications are used in business?
Q-26 How computer applications are used in Banking?
Q-27 How computer applications are used in Stock exchange?
Q-28 How computer applications are used in Retailing sector?
Q-29 How computer applications are used in education?
Q-30 How computer applications are used in medical field?
Q-31 How computer applications are used in Science?
Q-32 How computer applications are used in Product design and manufacturing?
Q33-What is a Programming language?
Q34-What is a difference between machine languages and assembly languages?
Q35- Why high level languages are more beneficial than low level languages?
(Write a note on High level Languages)
Q36- Write a note on the following languages.
Q37- Into how many generations the computer languages are divided.
Q 38-What is a compiler? How does it differ from an Interpreter?
Q: 39 Define the following.1-Source Program 2-Object Program
Chapter # 01 (Objectives)
EXERCISES
1.01 Complete the following statements.
(i) A modern computer is an electronic data processing device.
(ii) One of the first recognized calculating devices was the abacus.
(iii) Babbage is called the father of modern digital computer.
(iv) Pentium II is a fourth generation computer.
(v) Internet is a system of worldwide computer network for exchanging
information.
(vi) UPC stands for Universal Product Code.
(vii) Assembly language consists of short phrases of alphanumeric symbols called
mnemonics.
(viii) BASIC stands for Beginners All Purpose Symbolic Instruction Code.
(ix) Interpreter translates a symbolic language into Machine Language Code.
(x) In OOP text-based instructions are replaced by Symbolic Icon.
1.02 Tick (√) the following statements either True or False.
(i) Pascal used Napier’s idea of logarithm in Pascaline.
False
(ii) Fourth generation computers possess the ability of AI False 15
(iii)Analoge computers are faster than digital computer.
(iv) Assembly language is HLL
True
False
(v) C is the most favorite language for writing Operating System. True
1.03 Encircle one choice A, B, C or D each of the Multiple choice questions.
(i) The first computer that used Vacuum tubes was:(A) Mark-1 (B) ENIAC (C) EDVAC (D) UNIVAC
(ii) Vacuum tube was invented in:(A) 1899 (B) 1906 (C) 1916 (D) 1926
(iii) Which of the following is called the first generation computer?
(A)Abacus (B) Pentium I (C) Mark I (D) UNIVAC
(iv) Transistor was invented in :(A)1943 (B)1947 (C) 1950 (D) 1952
(v) A translator is a :(A)System software(B)Low-Level Language(C)Translating machine(D)Application
software.
1.04 Match the items given in Column I with those given in Column II
Column I Column II Answer
i)
ADA a) Fifth Generation iii)
ii)
Operating System b) 4GL iv)
iii) Artificial Intelligence c) CAD vii)
iv) Visual Basic d) CAI ix)
v)
Transistor e) LLL viii
vi)
Microprocessor f) Translator x)
vii) Software g) Real Time i)
viii) Machine Language h) C ii)
ix) Teaching/Learning i) VLSI vi)
x)
Compiler j) Second Generation v)
_______________________________________________________
Computer Science – Pre-9
th
Chapter #02: Computer Components:
Q1. Define Computer ?
Ans:- A computer is an electronic data processing device. It reads data, processes it and
produces results accurately at very high speed.
Q2. Define computer system ?
Ans:- A computer along with a number of units attached to it (such as keyboard,
monitor, disk drive etc.) is known as a computer system.
Q3. Which are the two main divisions of a computer system ?
Ans:- Computer system have two major division:
1-Computer Hardware
2-Computer Software. 16
Q4.Describe the computer hardware ?
Ans:- Computer hardware are the physical components which are installed in a computer
box as well as the devices connected with it such as keyboard,monitor,mouse etc.
Q5. Write the names of different units of Main unit or system unit?
Ans:- Main unit or system unit consists of:
1-Control unit
2-Processing unit
3-Memory unit.
Q6. What are the peripheral devices?
Ans:- The devices that are attached with a system unit under the control of CPU are
called as the peripheral devices.
Q7.Name some common peripheral devices ?
Ans:- Some common peripheral devices are keyboard, mouse, monitor, printer and disk
drivers.
Q8.How peripheral devices help the main unit or system unit ?
Ans:- Peripheral devices help to communicate data / information with the system unit.
Q9.Which are the three major units of a computer system?
Ans:- Generally a computer system consists of the following three major units:
1-System unit 2- Input units (keyboard, mouse etc) 3-Outputs (monitor,
printer etc)
Q10.What are the functions of a computer system?
Ans:- A computer system performs the following functions:
1-Receive data and instructions for the system.
2-Stores the instructions and data to be used for processing.
3-Executes the instructions to process the data.
4-Transfer the result in form usable by human or other machines.
Q11. What is computer software?
Ans:- The technique or methods necessary to get the hardware to work are known
as computer software.
Q12.Which are the two types of computer software?
Ans:- Computer software can further be divided into :
1- System software
2-Application software
Q13. Given below is a digital computer organization. Complete and label it? 17
Q14.Draw the Block Diagram of a computer system with subunits of CPU. Also
name the various parts of a computer system?
Ans:- The system unit is the main unit of a computer system. It allows various
parts of the computer system to work together. A system unit consists of :
1-The central processing Unit ( CPU )
2-Semiconductor memory (Storage Unit)
3-Magnetic memory and disk drives
4-Adapters and connector
Q15.Describe the functions of CPU ?
Ans:- The central processing unit (CPU) is the brain of computer. It controls the
entire computer system and executes the instructions given to it. It consists
of Control Unit and Arithmetic & Logic Unit. It is located inside the system unit. 18
Q16.What are the functions of Arithmetic and Logic Unit (ALU)?
Ans:- Arithmetic and logic unit (ALU) contains a number of adder and logic gates in
addition to various types of registers. ALU performs all the processing in a CPU. It also carries
out arithmetic operations like addition, subtraction as well as logical operations. Registers such
as address registers, accumulation, instruction register, program counter etc. help the
computer to process data.
Q17.What are the functions of Control Unit (CU)?
Ans:- The control unit is the most important part of the CPU. It controls and coordinates
the activities of all the units of computer system. It performs this function by
issuing necessary commands to respective units of the computer.
Q18.What are memory registers? What are their functions?
Ans:- Both the CU and ALU require a small amount of temporary storage. These small
temporary storages or internal memory units hold the instructions and data
currently being processed. These small memory units are called registers. The
control fetches an instruction from RAM and stores it in an instruction register and
moves it to one of the ALU registers.
Q19.What is the difference between ROM and RAM?
Ans:- Read only memory (ROM) : Read only memory (ROM) is a permanent memory
of the computer. It handles many important tasks. One of these tasks is to provide
instructions to CPU during start up or booting process whenever the computer turned
on. Another important role of ROM which in turn supplies a character to be displayed
on the screen. ROM is nonvolatile memory i.e. the instructions stored on it cannot be
changed or deleted when the computer is turned off.
Random Access Memory ( RAM ) : Random Access Memory (RAM) is major part of
the main memory. Any part of RAM id directly accessible to read / write data or
instructions on it. It is a fast memory but not permanent like ROM as it loses all of its
data and instructions as soon as the computer is turned off. Thus RAM is also called a
volatile memory.
Q20. Why computer memory (other than different registers of CU and ALU) is
necessary? Discuss the importance of main memory ?
Ans:- CPU contains registers which are small storage areas and a CPU needs much larger
space in mega-bytes as compared to registers that can hold a few bytes at a time.
Computers are equipped memory can hold programs and the data for current and
future use.
Main memory (Primary storage): Main memory consists of RAM and ROM built on 19
semiconductor chips. These are very fast and are directly accessible by the CPU. ROM is a
permanent memory of the computer. It handles many important tasks such as booting. While
RAM which is a major part of the main memory is a volatile memory and loses all of its data
and instructions as soon as the computer is turned off.
Secondary memory (Backing storage): secondary memories such as floppies, hard disks
and CD’s are used to increase the capacity of main memory. They can store a bulk of data /
information.
Q21. What is microprocessor? Name the electronics or electrical appliances in
which microprocessor is the is also used?
Ans:---- A microprocessor is the central processing unit of a computer without having a significant
amount of
memory. It is a Very Large Scale Integrated circuits (VLSI) developed on a single semiconductor chip. In
spite of
its small size a microprocessor chip contains thousands of electronic components. Microprocessors are
also used
in calculators, cameras, microwave ovens, washing machines, point of sale terminals, medical
equipments and
many other devices. In microcomputers CPU-board also called motherboard contains many chips for
other
components in addition to one or more microprocessor chips.
Q22. What types of buses are used in computer? What are their functions?
Ans:- In a computer system large amount of data and instructions have to move from one
unit to the other. This requires a system bus, which is a set of parallel wires. It provides an
electrical path among Control unit, ALU, Memory and other hardware parts and the
motherboard or attached circuit boards. Address data and control commands all flow along the
system bus through separate paths called the address bus, the data bus and the control bus
respectively.
The Data Bus: The data bus is an electrical path that connects the CPU, memory and the
other hardware devices on the motherboard. Each wire can transfer one bit at a time therefore
an 8-wires bus can move 8-bites or one byte at a time. A 16-bit bus can transfer 2 bytes at a
time and so on.
The Address Bus: An address bus connects the CPU with the memory. A CPU with 8-bit
address bus could address only 256 bytes of memory. Similarly a CPU with 16-bit address bus
can address 2= 65,536 bytes = 64 bytes = 64 Kbytes of memory and so on.
The Control Bus : The control unit controls the activities of all other units of the system. It
sends out control commands to all the units through control bus. Control unit direct the
transfer of data from main memory to arithmetic and logic unit (ALU) for processing. The
control bus provides a two-way transfer of data, instructions and the results between the main
memory and secondary storage.
Q23. What types of ports are used in computer? What are their functions?
Ans:- The receptacle at the back of a PC is called a port. A port provides a direct link for
external peripheral devices such as keyboard, mouse, monitor, printer etc via cables with the
computer’s common electrical bus. Most computers have several types of ports such as serial
port, parallel port and dedicated each with different capabilities and uses.
Serial Ports: A serial port provides a connection for plugging a peripheral device i.e. modem,
mouse etc, with one data line that carry one bit at a time and additional lines to carry control 20
signals. A serial port can have 9-pins or 25-pins. In personal computers serial ports are
generally designed as COM1, COM2, COM3 etc.
Parallel Ports :A parallel port provides a connection for transmitting fast flow of large
amount of data. Parallel ports allow 8 bits data at a time over a cable with eight separate data
line. Parallel ports can handle large volume of data at a much faster rate as compared to serial
ports. Parallel transmission is used to send data to the printer. The cable that connects two
parallel ports contains 25 wires, 8 wires carry data and remaining wires carry control signals.
In personal computers parallel ports are generally designed as LPT1, LPT2, LPT3 etc.
Q24. What in meant by Secondary Memory ( Backing Storage )? Mention some
Secondary storage devices .
Ans:- Secondary Memory (backing storage): Secondary memory also called as backing
storage is used to supplement the capacity of main memory. Secondary storages such as
Floppy disks, hard disks and CDs can store a bulk of data / information. The data in secondary
storage is first brought into the main memory before processing.
Q25. Where a microprocessor is located in a digital computer and how it works
with other components?
Ans:- A complete digital system including microprocessor (uP), program memory (ROM), data
memory (RAM) with other electrical components and input/ output (I/O) housed in a system
unit is called a microcomputer. In microcomputers CPU- board is called the main board or
motherboard where a microprocessor is located with basic circuitry and other components
such integrated circuits, transistors, diodes, resistors etc. Integrated circuits also called chips
along with the microprocessor chip are required in a system unit to store and process data.
Data moves from one chip to another along conducting line called a bus.
Q26. What is meant by the Main Memory ? mention some main storage devices?
:- Main memory of a computer is its internal memory also called primary memory. It
consists of RAM and Rom built on semiconductor chips. These are very fast and are directly
accessible by the CPU ROM is a permanent memory of the computer. It handles many
important tasks such as booting. While RAM which is a major part of the main memory is
volatile memory and loses all of is data and instructions as soon as the computer is turned off.
Different types of memory chips are available such as RAM (Random Access Memory ), Rom
(Read Only Memory), PROM ( Programmable Read Only Memory ) and EPROM (Erasable and
programmable Read only Memory) etc.
Q27. How the capacity of a storage device be expressed?
:- The capacity of a storage device is generally expressed in bytes. One byte is a group of
eight bits. A bit is a smallest memory unit that represents a binary digits. A bit has value either
0 or 1. For example: eight bits or one byte is used to represent a character. Thus 8000 bytes
memory means a storage capacity of 8000 characters.
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CHAPTER # 02 (Objectives)
EXERCISES Page 36
2.01 Complete the following statements
(i)A system unit of a computer consists of a CPU and Memory
(ii)CPU stands for Central Processing Unit.
(iii)ALU stands for Arithmetical and Logical Unit
(iv) Internal memory unit that are the small temporary storage of a computer are called
registered.
(v) A 16 bit bus can transfer 2 bytes at a time.
2.02Tick (√) the following statements either True or False.
i)The CPU of a computer is one of its input unit.
False
ii)The CPU of a system processes the data as instructed and sends the results to an output
unit.
True
iii)The Control unit carry out logical computation False
iv) Registers are the small storages the data that hold the Instructions and data currently being
in process.
True
v) One of the important function of RAM is to generate Characters. False
2.03 Encircle one choice A. B, C or D in each case.
i)which of the following are present in a system unit.
(A) I. II & III (B) II. & III (C) 1. II& IV (D) 1. II. Ill & IV
where (I) Input unit, (II) CPU, (III) Memory unit and (IV) Output unit
ii)RAM of a Computer is a:(A) Permanent storage (B) Secondary storage
(C) Primary storage (D) Backing storage
iii) The brain of an electronic computer is its:(A) CPU (B) CU (C) ALU (D) ROM
iv) An 8-bit address bus can address a memory of:(A) I Byte (B) 8 Bytes (C) 256 bits (D) 256 Bytes
v) Which of the following is not a semiconductor memory?
( A) ROM (B) RAM (C) PROM (D) None of these.
2.04 Match the items given in Column I with those given in Column II
Column I Column II Answers
i) Hard ware a) Booting Process v)
ii) Software b) LPT iv)
iii) Serial Port c) Physical Components of a
Computer system
i)
iv) Parallel Port d) Procedure necessary to
run the Computer
ii)
v) ROM e) COM iii)
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All questions for self Test
Computer Science (Ist Semester) Chapter # 02
Chapter #02: Computer Components:
Q1. Define Computer ?
Q2. Define computer system ?
Q3. Which are the two main divisions of a computer system ?
Q4.Describe the computer hardware ?
Q5. Write the names of different units of Main unit or system unit?
Q6. What are the peripheral devices?
Q7.Name some common peripheral devices ?
Q8.How peripheral devices help the main unit or system unit ?
Q9.Which are the three major units of a computer system?
Q10.What are the functions of a computer system?
Q11. What is computer software?
Q12.Which are the two types of computer software?
Q13. Given below is a digital computer organization. Complete and label it?
Q14.Draw the Block Diagram of a computer system with subunits of CPU. Also name the
various parts of a computer system?
Q15.Describe the functions of CPU ?
Q16.What are the functions of Arithmetic and Logic Unit (ALU)?
Q17.What are the functions of Control Unit (CU)?
Q18.What are memory registers? What are their functions?
Q19.What is the difference between ROM and RAM?
Q20. Why computer memory (other than different registers of CU and ALU) is
necessary? Discuss the importance of main memory ?
Q21. What is microprocessor? Name the electronics or electrical appliances in
which microprocessor is the is also used?
Q22. What types of buses are used in computer? What are their functions?
Q23. What types of ports are used in computer? What are their functions?
Q24. What in meant by Secondary Memory ( Backing Storage )? Mention some
Secondary storage devices .
Q25. Where a microprocessor is located in a digital computer and how it works
with other components?
Q26. What is meant by the Main Memory ? mention some main storage devices?
Q27. How the capacity of a storage device be expressed?
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