Gujarat Board Class 9 Solution Computer Chapter 4 Memory, Storage Devices and Data Representation Exercise Solution here in this Post.
Board |
GSEB Gujarat State |
Textbook |
9 Class |
Medium |
English |
Subject |
Computer Studies |
Chapter |
4 |
Chapter Name |
Memory, Storage Devices and Data Representation |
Gujarat Board Class 9 Computer Chapter 4 Memory, Storage Devices and Data Representation Solution:
1) What is computer memory?
Ans:- Computer memory is a part or storage place where the data or instructions which are feeded into computer are being stored. There are different types of computer memories but mainly two memories are used viz are i) Primary memory and ii) Secondary memory. The user can also access the data or instructions stored in the computer memory whenever it’s required but if it’s stored then only. Storing of data/instructions on the computer memory reduces the work feeding of data or instructions again and again in the computer system. storage capacity of computer memory is measured in bytes, kilobytes(kb), Mega bytes (Mb), giga bytes (gb) etc.
2) What is primary memory?
Ans:- Primary memory is also known as Main memory. Primary memory is used to quickly retrieve the stored data by the processor. Such memory is made up of cells, where a small amount of data is being stored on every cell. Every cell is being identified by a number, which is called as cell address, which is used to access the stored data. In primary memory the time which is required to store or access data from cell is independent of the cell address. Any location of the cell can be choosed for randomly use. Such type of memory is called as RAM (Random Access Memory). For ex. FIFO (First In First Out), LIFO (Last In First Out). In sequential memory, the data is been stored on a long string. If incase you want to access any part of the string you have go sequentially (visit the previous string) just like an audio tape (where if you want to hear the 3rd song, then you have to fast forward or access the first two songs). FIFO (First In First Out), is just like people standing in the queue which means the person standing at the very first of queue will be entertained /served first and last person standing will be entertained last. And LIFO (Last In First Out ) means a tray filled paper. The paper which is kept last in the tray comes first. The data stored on the primary memory is retained for a short period of time. The examples of primary storage devices are:- RAM (Random Access Memory), ROM (Read Only Memory).
3) What is secondary memory?
Ans:- Secondary memory is also known as Auxiliary memory. The data and instructions stored on the secondary memory is stored for a longer period/permanently. As compared to primary memory the secondary memory is much cheaper and slower. The data and instructions stored on secondary memory is not directly accessed by the processor but it requires I/O channels. Secondary memory has higher storage capacity. The data/instructions stored on the secondary memory remains unchanged, even if the power is turned off. Hence it is Non-volatile memory. The examples of secondary storage devices are:- Hard disk, CD (Compact Disk), DVD(Digital Versatile Disk), pendrives,.
4) Define bit. What are the symbols used to represent a bit?
Ans:- Computer does not understand human language. It only understands the language of numbers/digits 0 and 1 which is known as machine language/binary number system/binary language. Every single digit (0 and 1) in binary number system/binary language is called as Bit.
5) What are the measurement units for computer memory? What is the relationship between these units?
Ans:- Every single digit (0 and 1)in the binary language/binary number system is called as Bit, and when a group of 8 bits comes together they form a Byte. The measurement units for computer memory are as follows :-
1 bit = a single digit , either 0 or 1
8 bits = 1 byte, combination of 0’s and 1’s
1024 bytes = 1 KB (Kilobytes)
1024 KB (Kilobytes) = 1 MB (Megabyte)
1024 MB (Megabytes) = 1 GB (Gigabyte)
1024 (Gigabytes) = 1 TB (Terabyte)
6) Describe the following terms in one or two sentences?
Ans:- a) RAM:- The abbreviation of RAM is Random Access Memory. The data or instructions stored on RAM remains for short period of time. The data gets erased as the electricity is been turned off. Hence RAM is a volatile memory. RAM is a Read , Write memory.
b) ROM :- ROM stands for Read Only Memory. The data or instructions stored on such type of memory, does not gets erased even if the power supply is been turned off. It hods the data for a long period of time. RAM memory is permanent memory. The data which is written on ROM, can not be changed/ altered. It can be only read.
c) PROM:- It stands for Programmable Read Only Memory. They are manufactured as blank chips, which are used to write any data with the help of PROM programmer.
d) EPROM:- This is a type of memory which can erase the contents/data written on the PROM by exposing it to the ultraviolet light. EPROM stands for Erasable Programmable Read Only Memory.
e) EEPROM:- Instead of using ultraviolet light, this memory uses an electricity to erase the contents/programs stored on PROM. EEPROM abbreviation is Electricity Erasable Programmable Read Only Memory.
f) FIFO:- FIFO means First In First Out. The data is been accessed orderly in sequence. Ex. The first person standing in front of the queue will be entertained first, where as the person standing at the last of the queue will be entertained at last.
g) LIFO:- LIFO full form is Last In First Out, which can be termed the data is not accessed sequentially. Ex:- The piles of papers kept in a tray, where the last paper comes out first.
7) What is sequential access?
Ans:- In sequential memory if you want to access any part of the string you have go sequentially (visit the previous string) just like an audio tape (where if you want to hear the 3rd song, then you have to fast forward or access the first two songs).
8) What is RAM? How many types of RAM exist? Explain each in one line?
Ans:- RAM stands for Random Access Memory. The instructions or data stored on the RAM is retained/holds only for a temporary/short period of time till there is continuous supply of power. In the modern computers, RAM is always treated as Main Memory or Primary memory, where as CD, DVD, Hard disk, floppy disks will be treated as Secondary auxiliary devices. RAM also supports reading and writing operations. Data and Instructions can be stored when the RAM is been operated/ in used
There are mainly two types of RAM which are Static and Dynamic which are as follows:-
a) Static RAM:- It is popularly known as SRAM which does not needs to be refreshed thousands of times per second, which as result makes it more faster and much costlier as compared to Dynamic.
b) Dynamic RAM:- Dynamic RAM needs to be refreshed thousand of times per second. Dynamic RAM is slow and much cheaper than SRAM. Both of these RAMs are volatile in nature.
9) What is ROM? Where ROM is useful?
Ans:- ROM stands for Read Only Memory which means the data or instructions stored on ROM remains for a longer period of time. The programs written on ROM cannot be changed. ROM is a memory to store the instructions related to boot programs (programs that start up the system), printer driver files and fonts.
10) Distinguish between RAM and ROM?
Ans:-
RAM |
ROM |
RAM stands for Random Access Memory |
ROM stands for Read Only Memory |
The data/instructions stored on RAM memory gets erased when the power supply is been turned off. |
The data/instructions stored on ROM memory does not gets erased even the power supply is been turned off. |
RAM is volatile in nature. |
ROM is non- volatile in nature. |
It supports reading and writing operations |
It does not support write operations. Data only can be read not changed. |
Instructions are stored during its operation. |
Instructions are stored at a time of manufacturing. |
Static and Dynamic RAM are its types |
PROM, EPROM, EEPROM are it’s types |
11) What is cache? For what purpose it is useful?
Ans:- Cache is the special small and high speed storage/memory within the central processing unit of the computer system for frequent access. It deals with the increase in the processors speed. When the processor performs the task of read and write operations it first checks cache memory.
12) List any three secondary devices. Explain any one in brief?
Ans:- Following are the examples of Secondary devices are Hard disk, Compact Disk (CDs), Digital Versatile Disk (DVDs).
DVD (Digital Versatile Disk):- It is an optical disk used to store the data like movies with high quality and sound. DVD is just same like CD but it’s diffetent in dimensions. We can store the data in DVD upto 4GB in comparison of CD.
13) Explain how numbers are represented into computer memory?
Ans:- There are 2 ways to represent numbers into computer Memory which are 1) Decimal Number System and 2) Binary Number System
1) Decimal Number System:- It is also called as positional number system. For ex:- 246 will be written as 200+40+6. Ten symbols from (0-9) are called as digits in this system. We also make use of alphabets from (A-Z) .The combination of numbers and alphabets are called as Alphanumeric. Special character symbols like ($?@,) can also be used. All the digits, alphabets and symbols are arranged in a meaning ful way for communication, just different pattern of languages used for different disabled persons like Brail language used for blind persons etc.
2) Binary number system:- Binary number system is the language of 2 symbols as 0&1. Every single digit in this system is called as Bit.
14) Write a short note on IEEE floating point number representation.
Ans:- A real number can be represented by the 32 bit single precision method. IEEE stands for Institute of Electrical and Electronics Engineers which is the world’s largest and advanced association for the humanity’s benefit.
15) How images are represented into computer memory?
Ans:- The representation / feeding of images into the system is termed as digital image and the image is been converted into the symbols of 0’s and 1. The representation of images with the help of the digits , which can reset the position and size of the shapes like curves, squares, circles etc is termed to be as vector image representation. We can enlarge an vector image easily without shrinking or compromising with its quality. Vector images can represent fonts, logos and examples etc.
There’s another way to convert the image representation in memory is by dividing the image into the fixed number of rows and columns. Each cell in the image is known as pixel. Each pixel represents the quality of image or the brightness of a given at a specific place. If incase you divide the image by using many rows and columns, which will improve/increase the quality of the image. The set of pixels (two dimensional array)are normally stored in the computer memory in the form of raster image/map. Resolution is used for a counting of pixels in digital image. An image takes an amount of memory to store all its pixels. Images are always stored in computer memory.
Following are the image formats:-
.bmp- (Bit Map Image)
.jpg – ( Joint Photographic Experts Group)
.gif – (Graphics Interchange Formats)
.png – (Portable Network Graphics)
. tiff – (Tagged Image File Formats)
16) Choose the most appropriate option from those given below:-
1) What is an alternative name of a primary memory?
Answer: a) Volatileb.
2) For what amount of time does a secondary memory retains its content?
Answer: b) Long time
3) Which of the following is the unit of computer memory?
Answer: a) Bit
4) How many bits form a byte?
Answer: b) 8.
5) Which is an example of a LIFO?
Answer: c) Pile (tray) of paper.
6) Which of the following mechanism is used to erase the content of an EPROM?
Answer: a) ultraviolet light.
7) Which of the following type of memory is used by pen drives?
Answer: c) EEPROM.
8) Which of the following is a small and high speed memory within the computer central processing unit?
Answer: c) Cache.
9) Which of the following is not a secondary storage device?
Answer: a) Cache memory.
10) Which of the following number system is most suitable for basic computer data representation into machine readable form?
Answer: a) Binary.
11) Which of the following number system has 2 symbols 0 and 1?
Answer: b) Binary.
12) Which of the following method is used to represent an integer number into computer memory?
Answer: d) All of these.
13) Which of the following method is used to represent characters into computer memory?
Answer: d) All of these.