Solution of Question and Answer of Chapter 1

---:Solution of Question and Answer of Chapter 1:---

A. Tick [✓] the correct answer:

1. A scanner is an _______ device. 
• Ans: a. Input Device
2. Treating data according to the instructions and changing it into information is called, 
• Ans: b. Processing
3. CD-ROM and DVD-ROM are the examples of ______ device. 
• Ans: a. storage device
4. The hardware components that convey information to the user are called _____  device. 
• Ans: b. output.
5. ALU, CU and MU are the parts of _______ . 
• Ans: c. CPU

B. Write T for True and F for False statements.

1) A keyboard has two buttons on the top of it.	False
2) Joystick is mainly used to play games on a computer	True
3) The output or result we get on a paper is called softcopy.	False
4) We should move two fingers apart to zoom in the touchscreen.	True
5) The speed or inkjet printer is measured in lines per second.	False

C. Fill in the blanks.

    a. _____ is any data or instruction entered into the computer.

    Ans. Input

    b. Data that has been processed into a useful form is called______. 

    Ans. Output

    c. ______ printers have direct contact between printer head and paper.

    Ans. Impact

    d. Hard drives have storage capacities from ________ to_________.

    Ans. 500 GB, 8 TB

    e. The height and width of a memory card is usually no bigger than _______.

    Ans. 1.5 inches

D. Write the full form of the following.

    a. VDU : Visual Display Unit

    b. ALU: Arithmetic and logic unit.

    c. PPM: Pages Per Minute

    d. CPU: Central Processing Unit

    e. CU: Control Unit.

    f. LPM: Lines Per Minute

E. Define the following.

    a. Barcode reader:

    Ans: A barcode is a set of lines of different thickness that gives digital information about the product like its price, manufacturing date, etc. Barcode reader, also called a barcode scanner, is used to input data from barcodes.

    b. MICR:

    Ans: MICR reader is an input device used to read and identify magnetized characters printed on a document such as a bank cheque.

    c. Digicam:

    Ans: A digicam is an electronic input device used to capture and store photographs electronically in the computer.

    d. Pen drive:

    Ans: Pen drive is a computer storage device that is plugged in a USB (Universal Serial Bus) port on a computer. It has a storage capacity ranging from 512 MB to 100 GB.

F. Differentiate between the following.

a. Mechanical Mouse, Optical Mouse 

A mechanical mouse has a rubber ball on its underside. As the user moves the mouse around on the desktop, the ball rolls with these movements. This detects the mouse movement in any direction.

An optical mouse however uses a red light emitting diode (LED) and an optical sensor in place of a ball or roller. Movement is detected by sensing changes in the reflected light.

b. Impact Printer, Non-impact Printer

Impact printers are those printers that have direct contact between printer head and paper. 

Non-impact printers are those printers that do not have direct contact between printer head and paper.

c. Recordable CD, Re-writable CD

A recordable CD is a multi-session compact disc used to record data. Data can be written on its each part only for once, and the disc contents cannot be erased.

A re-writable CD is an erasable disc that can be used to write multiple times. It acts like a hard disk, on which data can be written and rewritten multiple times.

G. Answer in 1-2 sentences.

    a. What is virtual keyboard?

    Ans: A virtual keyboard is a software component that allows an user to enter text  directly on-screen.

    b. What is motion input?

Ans: With motion input, a device containing a camera detects our gesture and then converts it to a digital signal that is sent to a computer or game device.

    c. Why should you prefer laser printer over Dot Matrix Printer?

Ans: Laser printer is a non-impact printer that uses laser technology to print on paper. It gives the best quality output. On the other hand, dot matrix printer is an impact printer that is slow in working, and is very noisy.

H. Answer briefly.

    a. How does a computer work?

    Ans: A computer is an electronic machine that works according to the instructions given by us. It works very fast and accurate. It does four main jobs. It inputs data, processes it, displays the output as information, and finally stores it.

    b. What is the use of storage devices?

    Ans: Storage devices enable us to store data and information. They can hold data, instructions, and information for future use.

    c. What is CPU and Name its units.

    Ans: Central Processing Unit (CPU) is the processing device of a computer. It receives the input from input devices, processes them and sends the result to the output devices. It consists of three units:

    ALU, Control Unit and Memory Unit.

(Following one is not need to write on note book)

I. Application based questions.

You went to a shopping center with your family. On the billing counter, there was a computer system. Which input and output devices you saw at the billing counter?

Ans: Input devices: keyboard, mouse, barcode scanner

        Output devices: monitor, printer