Right Bight Fourth Edition

Class 6^th

Lesson #1

 The Evolution of Computer

ANSWER THE FOLLOWING QUESTIONS

Q1. What is a computer? What is the difference between data and information?

Ans: A computer is an electronic data processing system. A computer receives input in the form of data. Processed data is called information.

Q2: Write a brief not on the different generations of computers.                           

Ans: (1) The computers of the first generation used vacuum tube. A vacuum tube consists of a glass bulb and a wire.

(2)Second-generation computers used transistors.

(3) Third-generation computers used an integrated circuit (IC).

(4) Fourth-generation computers are based on microprocessors.

(5) Fifth-generation computers are based on artificial intelligence (AL).

Q3: List five different places where computers are extensively used.

Ans :  Banks

          Factories

    Entertainment companies

    Medical professionals

   Law enforcement agencies

Q4: Beside each of the following,   write the data that is   being measured   or counted. State whether the device is analog or digital.

Device	Data	Type of device
A weather vane	Wind Direction	Analog
A mercury thermometer	Temperature	Analog
A  calculator	Mathematical operations	Digital

Lesson #2

 Input devices

ANSWER THE FOLLOWING QUESTIONS

Q1: Describe the different types of keys on a keyboard?

Ans : The different types of keys on a keyboard are alphabet keys , numeric keys and special keys.

Q 2. Name a place where the following input devices might be used:

a. Touch screen

A bank

b. Barcode reader

A department store

c. Card reader

An electronics store

d. Joystick

A gaming zone

e. RFID reader

A warehouse

f. Fingerprint reader

An office

Q3. Which of these is a pointing device?

a. Light pen

b. Card reader

c. Sensor

Ans: a. Light pen

Q4. Some students are physically challenged or have learning disabilities. Can you name two input devices that might help these students provide information to a computer?

Ans: Braille keyboards and voice recognition systems can help students who are physically challenged to provide information to a computer.

Q5. Which method of input (OMR, OCR, MICR, barcodes) is most likely to be used for each of the

following? Why?

Ans: a. Reading data from a lottery ticket

OMR. Data is read in the form of dots or marks.

b. Scanning a typed document into a word processor

OCR. An entire document is saved as an image.

c. Reading data from bank cheques.

MICR. Data printed in special ink is read using MICR.

Lesson #3

Output devices

 ANSWER THE FOLLOWING QUESTIONS

Q1. A microcomputer is advertised as having the following:

• 32 GHz processor

• 512 RAM

• 80 Gb hard drive

• 12-inch monitor

• Ink-jet printer

What output devices are mentioned in the advertisement?

Ans: A monitor and a printer are mentioned in this advertisement.

Q2. Explain the advantages of LCD monitors over CRT monitors.

Ans: LCD monitors are flat while CRT monitors are curved. The flat surface of LCD monitors makes it easy to view output. LCD monitors are lighter than CRT monitors. They do not flicker, which reduces the strain on the user’s eyes.

Q3. What are pixels? Explain screen resolution.

Ans: Pixels are picture elements. A computer screen can be divided into numerous small dots called pixels. These pixels make up an image on the screen. Screen resolution measures the amount of detail in which an image appears on the screen. A screen that has a greater number of pixels can display an image in greater detail.

Q4. What is a fax machine? How does it work?
 Ans: A fax machine is a device that combines input and output devices. We can use it to send and receive messages over telephone lines. A fax/modem board connects the computer with telephone lines. The user inserts a document into the fax machine and dials the number of the recipient. The fax machine scans the document and sends a copy of it over telephone lines to another fax machine at the receiving end. The receiving fax machine prints the copy or displays it on a monitor.
 Q5. Why are dot-matrix printers not used nowadays?
Ans: Dot-matrix printers are not used nowadays because they are slow, noisy, and produce low-quality output.

Lesson #4

Processing and storage

                                                  
   ANSWER THE FOLLOWING QUESTIONS

Q1. Define processing. What is the function of the central processing unit?
Ans: Processing is an activity performed by the computer by which data is transformed into information. The central processing unit processes data, stores it, and controls the operations of the other parts of the computer.
Q2. Name and briefly describe the components of the CPU.
Ans: The arithmetic logic unit (ALU) does all the arithmetic and logical operations needed to solve a particular problem. The control unit (CU) executes or carries out all the instructions which have been stored in the memory. The memory unit (MU) stores data and instructions.
3. What is an SD memory card? Why is it called a solid-state storage device?Ans: An SD memory card is an optical secondary storage device that stores data in gigabytes. It is smaller, lighter, and easier to                                     carry around than other storage devices. An SD memory card is called a solid-state storage device because it does not have any moving parts.
Q4. What is the difference between primary and secondary storage?
Ans: Primary storage is located within the system unit while secondary storage is located outside the system unit. Secondary storage is removable storage. It can be removed from one system unit and attached to another. Primary storage has less capacity than secondary storage. Secondary storage stores data permanently.
Q5. Draw a table and differentiate between RAM and ROM.

RAM ROM
Ans: 1. RAM stands for random-access memory. 1. ROM stands for read-only memory.

2. RAM is temporary memory. 2. ROM is permanent memory.

3. Data stored on RAM can be changed. It is also called volatile memory.

3. Data stored on ROM can be read but cannot be changed. It is also called nonvolatile memory.

Lesson #5

Operating system and user interface

   ANSWER THE FOLLOWING QUESTIONS                                          

Q1. What is software? What are the two main types of software?
Ans: Software is a set of programs that guides a computer in performing related tasks. The two main types of software are system software and application software.
Q2. What is the purpose of an operating system?          
Ans: The purpose of an operating system is to make sure that the computer is running properly and performing routine tasks.
Q3. What is the difference between integrated software and application software?
Ans: Application software is software designed to do a specific job. Integrated software combines all the major types of application software and brings them together in one application.
Q4. What is a user interface? Write a brief note on the two commonly-used interfaces.
Ans: A user interface is the way in which a user gives commands or instructions to the computer and the way in which the computer displays information back to the user.
There are two commonly-used interfaces:

A. Command Line Interface (CLI)

A command line interface allows a user to give data and instructions to a computer by typing them on a keyboard. DOS is an example of an operating system that is based on command line interface.

B. Graphical User Interface (GUI)

A graphical user interface provides a way for the user to communicate with the computer through visual images.

Q5. Explain two problems with using a command line interface.

Ans: There can be some problems with using a command line interface. Users have to learn the syntax for each instruction. Also, a command line interface is not very attractive or interesting to use.