CBSE Computer-Class-VIII(Solved Exercise-1):

Solved Exercise

Class-VIII-Chapter-1

A. Multiple choice questions:
1. Binary digits combine to form a number called as binary.
a. source b. unit c. code d. digit
Answer: Code
2. One byte contains:
a. eight bits b. five bits c. six bits d. seven bits
Answer: Eight bits
3. Chip sets are made up of tiny pieces of a material called.
a. iron b. silicon c. copper d. bronze
Answer: Silicon
4. The hard disk is a spindle of magnetic disks called.
a. plotters b. slots c. platters d. sectors
Answer: Platters
5. It is connected to the computer through the USB port of cabinet.
a. Pen drive b. hard drive c. soft drive d. compact drive
Answer: Pen drive
6. Data can be recorded either on one side or both the sides of the .
a. CD b. DVD c. pen drive d. floppy
Answer: DVD

B. Write T for true and F for false:
1. Floppy disks are typically 3.5" in size (diameter) and can hold 1.44 MB of data.
Answer: T
2. Compact disk is portable disk having data storage capacity between 650-700 MB.
Answer: T
3. Storage capacities of hard disks for personal computers range from 20 GB to 500 GB.
Answer: T
4. DVD has smaller storage capacity as compared to CD.
Answer: F
5. We should write with pen or pencil on the shining side of a CD/DVD.
Answer: F

C. Fill in the blanks.
1. In short, a binary digit is called a ________________.
Answer: Bit
2. The byte was originally developed to store a _________________.
Answer: Single character
3. Each _________ has a collection of chips and controllers known as the chip set.
Answer: Motherboard
4. The PCBs are also called _______________ which are attached to the motherboard.
Answer: Daughter board
5. All the instructions stored in ROM can only be _____________.
Answer: Read
6. The amount of data can be stored in secondary memory is called its ______________.
Answer: Capacity

D. Match the following
1. Primary memory a. Hard disk
2. Chip set b. 8 bits
3. Megabyte c. Silicon
4. Secondary memory d. 1024 bytes
5. Kilobyte e. RAM
6. Byte f. 1024 KB
Answer:
1.--e
2.--c
3.--f
4.--a
5.--d
6.--b

E. Answer the following questions in short.
1. Write the types of Primary memory.
Answer: There are two types of primary memory.
a. RAM(Random Access Memory)
b. ROM(Read Only Memory)

2. Name four secondary memories.
Answer: Secondary memories:
1. CD
2. DVD
3. Hard disk
4. Floppy disk

3. Write precautions, we must follow while using a CD/DVD.
Answer: Precautions:
1. When we are not using a CD/DVD keep it in its cover.
2. Do not touch the shining side of a CD/DVD.
3. Do not bend a CD/DVD

4. Write down two main categories of memories.
Answer: There are two categories of memories.
1. Primary memory
2. Secondary memory.

5. What is pen drive?
Answer: Pen drive is a small, pen like device. It is portable in size. It is attached to the computer through the USB port of cabinet.

F. Answer the following questions in detail.
1. What is memory? Write about its usage.
Answer: The place where data and instructions are stored is called the memory of the computer.
Memory usage:
Just like a human brain, computer need memory to store data. Computer memory is the storage space in computer where data to be processed and instructions required for processing are stored.

2. What is memory card? Explain.
Answer: Memory cards are a type of storage media that is most commonly used in digital cameras, handheld computers, MP3 players, cell phones, game consoles, and printers, to store pictures, videos, music and other data.

3. What is floppy disk? Explain.
Answer: These are small removable disks that are plastic coated with magnetic recording material.
Floppy disks are typically 3.5" in size and can hold 1.44 MB of data.This portable storage device is a rewritable media and can be reused a number of times.

4. What is CD? Explain it types.
Answer:The full form of CD is compact disk. It is round in shape and can store the data and programs.
There are two kind of CDs. -
CD-R: Compact disk readable. In this type of CD, data can be written only once.
CD-R CD -RW: Compact disk Rewritable. In this type of CD, data can be written multiple times.

5. What is external hard disk drive? Write its advantages.
Answer: A hard drive is a computer component that holds data. Every computer needs at least one hard drive to store it s operating system, programs and user information.Usually this drive is internal, or built into the computer, but as computer systems have evolved and different needs, threats and circumstances have arisen, external hard drives have become more popular.