9th Computer Science | Chapter # 1 | Short Questions | Answers | Notes | All boards of Punjab

1.    What is difference engine?

Ans.            Charles Babbage, a mathematics professor in Cambridge, England designed an automatic mechanical calculating machine that was work with steam powered and fully automatic. He named this machine as difference engine.

2.    Write any two characteristics of the third generation of computer.

Ans. .(a) Integrated circuits were used in these computers.

(b) Computers became smaller in size and faster in speed.

3.    What is the use of laptop computer?

Ans.            It is a portable computer. It can run all the same software as runs on desktop computers. They work in the absence of electricity as they have expensive battery packs.

4.    Define Computer.

Ans. Computer is an electronic device that processes data and converts it into useful

        information.

5.    What is the role of Pascal in invention of Computer?

Ans. Pascal invented a machine that had a system of gears known as Pascaline calculator. Numbers could be entered and cumulative sums obtained by cranking a handle. This calculator had not provided sufficient precision for practical use.

6.    Define Language Translator.

Ans.            It is a program that translates high level language into machine code.

7.    Write four names of High Level Language.

Ans.            Java, Visual Basic, C/C++, COBOL

8.    Write two advantages of transistor.

Ans.            i.          Much less expensive than a vacuum tube.

        ii.         Do not get hot and burn out like a vacuum tube.

9.    In which computer, the characteristics of Analog and digital computer exist?

Ans.            Hybrid computers are the combination of analog and digital computers. They use analog to digital and digital to analog conversion. These computers can produce highly accurate and precise results. These types of computer are used in robotics, medical labs etc.

10.  Write the purpose of main frame computer.

Ans.            These computers are used in the organizations where many people need frequent access to the same data e.g banks, airlines etc.

11.  Write two positive effects of internet on Society

Ans.            Uses of internet are:

i)                   To connect with people all over the world and bring them closer to each other e.g face book.

        ii)        It provides wealth of knowledge on every topic.

12.  What is abacus?

Ans.            It is wooden rack holding horizontal wires with beads strung on them. When these beads are moved around according to programming rules, all arithmetic problems can be done.

13.  Who was John Napier?

Ans.            John Napier was a Scottish mathematician who created logarithm table to facilitate calculations. He also created a device using rods, also called Napier’s bones to perform arithmetic calculations.

14.  How did microprocessor affect computer?

Ans.            With the invention of micro processor, internal storage of computer has been increased. Now computers have high processing speed and become smaller in size. Micro processors are used in many electronic devices such as wrist watches, microwaves oven and cars.

15.  Define pocket computer.

Ans.            It has been designed to allow people to keep lots of information close to hand whenever we are travelling.

16.  Define internet.

Ans.            It is a collection of millions of computers connected with each other to share data. It is aglobal computer network providing a variety of information and communication facilities.

17.  How many types of computer?

Ans.            There are three types of Computer.

            (a)Analog computer b)    Digital Computer          c)   Hybrid Computer.

18.  How many language translators?

Ans.            The language translator can be categorized into three main types

            (a)       Assembler     (b)       Compiler        (c)       Interpreter

19.  What did Pascal invent?

Ans.            Pascal invented a machine that had system of gears. Numbers could be entered and cumulative sums obtained by cranking a handle. It was known as Pascal’s Pascaline Calculator.

20.  Which technology was used in second generation computers?

Ans.            The major change in second generation computers was the replacement of vacuum tube with transistors.

21.  What are super computers?

Ans.            They are the most powerful computers which are built to process huge amount of data, perform complex calculation, help analyze and forecast global weather patterns. They can perform more than 1 trillion calculations per second.

        Example Cray-90.

22.  What do you mean by Hybrid Computer?

Ans.            These computers are the combination of analog and digital computers. These are used in robotics, medical labs etc.

23.  Explain UNIVAC.

Ans.            It was the first successful computer developed for commercial use by Eckert and Machly in 1947. It was intended for both scientific and commercial use as well as in education field.

24.  Describe the two uses of computer in Education Field.

Ans. i)  A large number of learning programs are available on almost every subject.

ii) The examinations can be conducted throughout the world.

25.  Who is a Charles Babbage?

Ans.            Charles Babbage was a professor of mathematics in Cambridge England who first developed difference engine and then designed a general purpose fully program controlled digital computer analytical engine.

26.  What is Electronic Digital Computer?

Ans.            In 1942, John P Eckert John Wr. Mawchly at the Moore school of Electrical Engineering University of Pennsylvania built a high speed electronic digital computer to do the job. This machine was known as ENIAC (Electrical Numerical Integrator And Calculator).

27.  What is basic difference between Vacuum Tube and transistor?

Ans.           

Vacuum Tubes	Transistors
They were expensive because of the amount of material.	200 transistors are about the same size as one vacuum tube in a computer.
Skill needed to manufacture them.	Much less expensive than a vacuum tube.
They get hot and burn out.	It can work 40 times faster than vacuum tube.
Air conditions were needed to hour them.	Do not get hot and burn out like a vacuum tube.

28.  Differentiate between Laptop and Desktop Computers.

Ans.           

Laptop computers	Desktop computers
They are portable.	They are not portable.
They are more expensive than desktop computers.	Much less expensive than a vacuum tube.
They work in the absence of electricity as they have expensive battery packs.	They do not work when electricity goes off.

29.  Differentiate between analog and digital computer.

Ans.           

Analog Computer	Digital Computer
They process data in graphical form using electronic or mechanical phenomena.	They process data in numerical form using digital circuit.
They are used in solving dynamic problems.	It can perform only one calculation at a time.

30.  Write down any three positive impacts of computer and internet on society.

Ans.            .(a)  Education institutions use computers for various learning activities

(b) Questions are marked by the computer which minimize the chance of committing mistakes.

        (c)   Computers are used to keep track of huge transactions

31.  Define high level language.

Ans.            These are close to human languages and far from the machine language. These are machine independent. e.g, C/C++, Java, BASIC etc.

32.  What is terminal?

Ans.            A terminal is a monitor and a keyboard connected to a main frame.

33.  What do you mean by micro computer?

Ans.            Micro computers also called PCs are typically developed for individual users. These are less powerful machines.

34.  What is Von Neumann Theory?

Ans.            According to Von Neumann Theory “Data and program can be stored in the same memory. Thus the machine can itself alter either its program or internal data.”

35.  What is the use of Laptop Computer?

Ans.            It is a portable computer. It is much more expensive than desktop computers. It has expensive battery packs. It has same type of operating system as desktop ones. It has a full sized keyboard and a touch sensitive pad.

36. What do you know about COBOL?

Ans.            COBOL stands for Common Business Oriented Language. It was designed as the language for businessmen. Its only data types were number and string of text. COBOL statements also have a very English like grammar making it quite easy to learn.

37.  What is the idea of Modem Stored Program?

Ans.            Data and program can be stored in the same memory. Thus the machine can itself alter either its program or internal data. This idea is usually referred to as stored program.

38.  Write some advantages of Transistors.

Ans.               i.       Much less expensive than a vacuum tube.

               ii.      Do not get hot and burn out like a vacuum tube.

39.  Define  BASIC  Language,

Ans.            BASIC stands for Beginner’s All Purpose Symbolic Instruction Code. It was designed to allow students to write programs. It responds fast for small programs.

40.  Describe the use of Java language.

Ans.            Java is a well known technology which allows you for software designed and written  only once for an  "virtual machine" to run on a different  computers, supports various Operating System like Windows PCs, Macintoshes, and Unix computers. Java enable us  to play online games, video, audio, chat with people around the world, Banking Application, view 3D image and Shopping Cart.

41.  Write the advantages of simulation.

Ans.            Advantages of Simulation

Ø  Computer simulation are widely used in educational institute to make clear the understanding of the working of various system.

Ø  It allows students to do more complicated and hazardous experiments, obtain results more quickly and get a deeper understanding of the experiment.

Ø  Simulation of aeroplane  make, the pilot clear the working of various parts of aeroplane

     42.  How is started of computer's history?

Ans.            The history of computer  starts out about 5000 years ago, with the birth of abacus. It is a wooden rack holding horizontal wires with beads strung on them. All arithmetic problems can be done by moving these beads.

43.  Differentiate between first and second generation of computer.

Ans.           

First Generation	Second Generation
Vacuum tubes were used in this generation	Transistors were used in this generation.
Vacuum tubes get hot and burn out.	Transistors do not get hot and burn out. Like vaccum tube.
Computer of this generation were very large machine.	Computer were smaller and had high processing speed.

44.  What is meant by first generaton of computer?

Ans.            Computer of this generation used vacuum tubes to perform calculation. Computers of this generation were very large machines. Special rooms with air conditioning were needed to house them because of the heat generated by vacuum tubes. The most important computers were ENIAC and UNVAC-1

45.  Define Mini computer?

Ans.           

·     They got their name because of their small size.

·     They have less processing power than main frame computers.

·        They have high processing power than micro computers.

·        They can support number of user’s input and output requirements.

·        They are used in network environment as server machines.

·        HP 3000 is an example of minicomputer.

46.  What is meant by interprete?

Ans.            It is a language translator That translate the source code into machine code line by line.

47.  Write any four examples of Computer Application.

Ans.            Some applications of computers are:       

(a) Controlling space flight

(b) Landing Airplanes

(c) Printing books

(d)  Modern stores used computer system to generate receipt and the customs pay the bill

48.  Write fifth generation, shortly.

Ans.           

v Fifth generation computing devices are based on artificial intelligence.

v This generation develops devices that respond to natural language input and are capable of learning and self organization.

v Voice recognition system is being used today.

v Quantum computation and molecular and nano technology have changed the face of computers in years to come.

49.  Define machine language.

Ans.            A type of language in which instructions are written in binary form is called machine language. It is the only language that is directly understand by the computer. It is the fundamental language of the computer. It is difficult to understand for humans.

50.  Who invented difference engine?

Ans.            Charles Babbuge, a mathematics professor in Cambridge England invented difference engine.

51.  ENIAC and UN!VAC stands for what?

Ans.            ENIAC: Electronic Numerical Integrator and calculator.

        UNIVAC: Universal Automatic Computer

52.  What is Barcode?

Ans.            The items at store are marked with Bar code. This is called as Universal Product Code. This is a sequence of lines which is read by a Bar Code Reader. The Price of the item is stored in this code and these are automatically added to the bill.

53.  Write two characteristics of mini computer.

Ans.              (a)     Mini computer got their name because of their small size.

(b)     They have less processing power than mainframe computers but high  

           processing power than micro-computers.

(c)     They are less expensive than mainframe computers.

  (d)     They are used in networked environment as server machines. (HP-3000)

54.  How were punched cards used?

Ans.            The punch card tabulator could read information that had been punched into cards. These cards were maintained in stack form. Solutions to different problems could be stored on different stacks of cards and accessed when needed.

55. Define Fortran.

Ans.            FORTAN stands for Formula Translation. It was introduced in 1957. It was the major high-level programming language. Its was designed at IBM for scientific computing was mainly used to solve mathematical problems in physics and mathematics.

56.  Define microprocessor.

Ans.  Microprocessor is a complete processing circuit on a chip. It contains thousands of  ICs. Ted Hoff produced the first microprocessor in 1971 for Intel.                                        

57   State the structure of Analogue computer.

Ans.            An analog  computer recognizes data as continuous measurement of physical property. Voltage, pressure, speed and temperature are some physical properties that can be measured in this way. Slide rule, curvimeter, plainmeter and harmonic analyzer are early special-purpose analog computers.

58.  State the use of laptop computer.

Ans.            A laptop is a mobile computer that has keyboard, screen and other devices integrated into a single compact case. It is designed to fit in the lap. It has batteries and can be used for many hours without continuous power supply.

59.  Write any two function of fourth generation.

Ans.            The fourth generation computers started with the invention of microprocessor. The microprocessor contains thousands of ICs.Ted Hoff produced the first microprocessor in 1971 for Intel. It was known as Intes 4004.

60   Write the utility of pocket computer.

Ans.            Pocket computer is also known as palmtop computer or handheld computer. It fits in the hand of user easily. It contains small and light batteries that can be recharged. It does not have full size keyboard. It contains small screen and small keyboard.

  

61.              Distinguish between High level and Low level languages.                

Ans.

        High Level Language:-  High level language are close to human language and far from the machine language. These are machine independent languages.

        Low level language:-          Low level languages are close to machine languages and far from human languages. This is machine dependent language.

62. What do you know about ENIAC?                                

Ans.  ENIAC stands for Electronic Numerical Intergrator and Calculator. It was the first general purpose electronic digital computer designed by Jhon William Machly and John Eckert in 1942. It was very heavy and large in size. It consumed 140 kilo watts of power. It can do 5000 additions per second.

63.  Define Desktop Computer.                                  

Ans.   The computer that can be placed on a desk is called a desktop computer. There are two main types of desktop computer.

        1-        The Macintosh (made by Apple computers)

        2-        Personal computer (PCs) usually made by IBM computers.

64. State the applications of computer in retailing applications.

Ans.              Modern stores use computer to prepare bills using bar code reader at great speed. They accept creddit cards. They also update teh inventory list and help the store manager to see which items are short. Marketing expers can also use this information.

65. What is Program Language?                  

Ans. A program language defines a format for writing instructions in a specific order which are to be executed by   computer. Programing langauges provide a  framwork work for expressing algorithms and are a way of communicating with the computer.