ch-1 computer peripherals

Class VII

Chapter 1                             Computer Peripherals

G. Short answer type questions:-

1. What is an Operating System ?

Ans. An Operating System is the software that manages the computer’s resources and executes application programs.

2. What do you mean by Peripheral devices ?

Ans. Peripheral devices are defined as auxiliary devices such as a computer mouse or keyboard that connects to and works with the computer in some way. Other examples are microphones, loudspeakers, webcams, and digital cameras.

3. What is a scan code ?

Ans. When any key from the keyboard is pressed , the microprocessor generates a number called the Scan Code.

4. What is a Hard Copy ?

Ans. The output given by a printer is called as a hard copy .

5.Write a short note on Line Printer ?

Ans. Line printers produce output by printing one line at a time. They cannot print graphics.

H. Long  answer type questions:-

Q1. What is a Computer system ?

Ans.A computer system is a combined set of hardware and software designed to process data and produce a meaningful result. Every computer performs the basic functions of input, output , process ,storage and transfer of data .

Q2. Explain Hard Disk ?

  Ans. Hard Disk holds a large amount of data than a floppy disk. A hard disk is made up of stacks of disks called platters. These platters are stacked vertically on a common axis. Surface of each platter is coated with a magnetic material .All the disks except outer portion of top and bottom disks are used to store data.

 

Q3. Write a note on CD-ROM .

Ans. CD – Rom (Compact Disk – Read Only Memory )

It is a small spiral disk from which data is  retrieved using a laser beam .The data  stored in it cannot be changed but can only be read .CD – ROM is made up of pits and lands .CdD-ROMs can hold upto 700 MB data .

Diagram:-

From the book

Q4.How Impact Printers are different from Non – Impact printers ?

Ans.                   

	Impact	Non-Impact
1	. It prints characters or images by striking print hammer or wheel against an inked ribbon.	1. It prints characters and images without striking the papers.
2	Are of  two types : 1.Line Printers 2.Character Printers	Are of two types 1.Inkjet Printers 2.Laser Printers
3	Its speed is slower.	Its speed is faster.

4. Its printing quality is lower.	Its printing quality is higher.
5  It generates noise during printing.	It does not generate noise during printing.
6. It uses inked ribbon for printing.	It uses toner or cartridge for printing.
7 It is less expensive.	It is more expensive.
8  Dot matrix is an impact printer.	Laser printer is a non-impact printer.