Kerala Plus One Computer Science Chapter Wise Previous Questions Chapter 3 Components of the Computer System
Question 1.
Which software is used for calculation? (Say – 2015)
a) Word processor
b) Spreadsheet
c) Presentation
d) Multimedia
Answer:
b) Spreadsheet
Question 2.
Accumulator stores (Say – 2015)
a) address of data
b) instruction to be executed
c) address of next instruction to be executed
d) intermediate result
Answer:
d) intermediate result
Question 3.
If Tracks and Sectors: Hard disk, then ………….: Compact disk (March – 2016)
Answer:
Pits and Lands (OR) 0 and 1
Question 4.
Which one of the following file extensions is different from others? (Say – 2016)
a) WAV
b) MP3
c) PNG
d) MIDI
Answer:
c) PNG, the others are audio files.
Question 5.
Which register holds the memory address of the next instruction to the executed? (Say – 2016)
a) Accumulator
b) PC
c) MBR
d) MAR
Answer:
b) PC
Question 6.
a) Write the following memory devices in the order of their speed. (fastest to slowest order) (March – 2017)
i) Cache
ii) RAM
iii) Hard Disk
iv) Registers
b) What do you mean by Freeware and Shareware?
Answer:
a) i) Registers
ii) Cache
iii) RAM
iv) Hard Disk
b) Freeware : A s/w with Copy right is available free of cost for unlimited use.
Shareware : It is an introductory pack distribUted on a trial basis with limited functionality and period.
Question 7.
a) What do you mean by cache memory? (March – 2015)
b) Write the names of the figures given below.
Answer:
a) It is a high-speed memory placed in between the CPU and RAM. CPU is a high-speed memory compared to RAM. There is a speed mismatch between the CPU and RAM to resolve this problem a high-speed memory called cache memory is placed in between the CPU and RAM
b) QR code and Bar Code
Question 8.
Explain how e-waste creates environmental and health problems. What are the different methods for e-waste disposal? Which one ¡s the most effective in your point of view? Why? (March – 2015)
Answer:
e-Waste(electronic waste): It refers to the malfunctioning electronic products such as faulty computers, mobile phones, tv sets, toys, CFL, batteries etc.
It contains poisonous substances such as lead, mercury, cadmium etc. and may cause diseases if not properly managed.
A small amount is recycled. Due to this our natural resources are contaminated(poisoned). Some of them can – recycle properly. But it is a very big problem in front of the Government to collect segregate, recycle and disposal of e-Waste.
e-Waste disposal methods
a) Reuse Reusability has an important role of e-Waste management and can reduce the volume of e-Waste
b) Incineration: It is the process of burning e-Waste at high temperature in a chimney
c) Recycling of e-Waste : lis the process of making new products from this e-Waste.
d) Landfilling: It is used to level pits and cover by thick layer of soil.
Question 9.
What do you mean by e-waste? Explain the role of students in e-waste disposal. (Say – 2016)
Answer:
e-Waste (electronic waste) : It refers to the malfunctioning electronic products such as faulty computers, mobile phones, tv sets, toys, CFL etc. It contains poisonous substances such as lead. mercury. cadmium etc and may cause diseases if not properly managed.
Students’ role in e-Waste disposal
- Stop buying unnecessary electronic equipment
- Repair Faulty electronic equipment instead of buying a new one.
- Give electronic equipment to recycle
- Buy durable, efficient. quality, toxic-free, good warranty products
- check the website or call the dealer if there is any exchange scheme
- Buy rechargeable battery products
Question 10.
To use a computer not only the hardware but also software are required. Explain the classification of software. (Say – 2015)
Answer:
Software : The set of instructions that tell the hardware how to perform a task is called software: Without software computer cannot do anything. Two types System 51w and Application s/w System software :
It is a collection of programs used to manage system resources and control its operations. it is further classified into two.
a) Operating System b) Language Processor
a) Operating System : It is collection of programs which acts as an interface between user and computer. Without an operating system computer cannot do anything. Its main function is make the computer usable and use hardware inan efficient manner. eg: – Windows XP, Windows Vista. Linux, Windows 7, etc.
Major functions of an operating System
- Process management: It includes allocation and deallocation of processes(program in execution) as well as scheduling system resources in an efficient manner
- Memory management: It takes care of allocation and de allocation of memory in an efficient manner
- File management: This includes organizing, naming , storing, retrieving, sharing , protecting and recovery of files.
- Device management: Many devices are connected to a computer so it must be handled efficiently.
b) Language Processes : We know that a program is a set of instructions. The instructions to the computer are written in different languages. They are high level language (HLL) and low level language. In HLL English-like statements are used to write programs. They. are C, C++, COBOL, PASCAL, VB, Java etc. HLL is very easy and can be easily understood by the human being.
Low-level language are classified into Assembly Language and Machine Language.
In assembly language mnemonics (codes) are used to write programs
eg: – ADD – A,B – A = A+B
SUB – A,B – A = A – B
INC – A – A = A + 1
In Machine Language 0’s and 1 ‘s are used to write program. It is very difficult but this is the only language which is understood by the computer. Usually programmers prefer HLL to write programs because of its simplicity. But computer understands only machine language. So there is a translation needed. The program which perform this job are language processors. The different language processors are given below:
- Assembler: This converts programs written in assembly language into machine language.
- Interpreter: This converts a HLL program into machine language by converting and executing it line by line. The first line is converted if there is no error it will be executed otherwise you have to correct it and the second line and so on.
- Compiler: It is same as interpreter but there is a difference it translate HLL program into machine language by converting all the lines at a time. If there is no errorthen only it will executed.
II. Application Software
Programs developed to serve a particular application is known as application software. eg:
MS Office, Compression Utility, Tally etc.
Application software can further be sub divided into three categories.
a) Packages
b) Utilities
c) Customized Software
a) Packages: Application software that makes the computer useful for people to do every task. Packages are used to do general purpose application.
They are given below:
1) Word Processes : This is used for creation and modification of text document. That means a word processor helps the people to create. edit and format a textual data with less effort and maximum efficiency. By using word processor we can change font and font size of character. change alignment (left, right, center and justify). check spelling and grammar of the whole document etc. eg: – MS Word.
2) Spread Sheets: It contains data or information in rows and columns and can perform calculation (Arithmetic, Relational and logical operation). It helps to calculate results of a particular formula and the formula can apply different cells (A cell is the intersection of a row and column. Each column carnes an alphabet for its name and row is numbered). It is used to prepare budgets, balance sheets, P & L account, Pay roll etc. We can easily prepare graphs and charts using data entered in a worksheet. A file is a work boQk that contains one or more work sheets. eg : – MS Excel is a spread sheet software.
3) Presentation and Graphics : You can present your idea with sound and visual effects with the help of presentation software by preparing slides. The application software that manipulate visual images is known as graphics software. Eg: – MS Power Point is a presentation package.
4) Data base package : Data base is a collection of large volume of data. DBMS is a set of programs that manages the datas are for the centralized control of data such that creating new records to the database, deleting, records whenever not wanted from the database and modification of the existing database. Example for a DBMS is MS Access.
5. DTP Packages : DTP means Desk Top Publishing. By using this we can create books, periodicals, magazines etc. easily and fastly. Now DTP packages are used to create in Malayalam also, eg: – PageMaker.
6) Utilities : Utilities are programs which are designed to assist computer for its smooth functioning. The utilities are given below:
- Text editor: It is used for creating and editing text files.
- Backup utility : Creating a copy of files in another location to protect them against loss, if your hard disk fails or you accidentally overwrite or delete data.
- Compression Utility : It is used to reduce the size of a file by using a program and can be restored to its original form when needed.
- Disk Defragmenter: It is used to speeds up disk access by rearranging the files that are stored in different locations as fragments to contiguous memory and free space is consolidated in one contiguous block.
- Virus Scanner: It is a program called antivirus software scans the disk for viruses and removes them if any virus is found.
c) Specific purpose software (Customized software): It is collection of programs which are developed to meet user needs to serve a particular application. It is also called tailor made software.
Question 11.
Describe the different types of memories and memory devices in computers with features and examples. (March – 2016)
Answer:
Memory
Storage Unit(Memory Unit): A computer has huge storage capacity. It is used to store data and instructions before starts the processing. Secondly it stores the intermediate results and thirdly it stores ‘ information(processed data), that is the final results before send to the output unit(Visual Display Unit, Printer, etc)
Memory measuring units are given below.
1 bit = 1 or 0(Binary Digit)
4 bits = 1 Nibble
8 bits = 1 Byte
1024 Bytes = 1 KB(Kilo Byte)
1024 KB = 1 MB(Mega Byte)
1024 MB = 1 GB(Giga Byte)
1024 GB = 1 TB(Tera Byte)
1024 TB = 1 PB(Peta Byte)
Two Types of storage unit
i) Primary Storage alias Main Memory: It is further be classified into Two – Random Access Memory (RAM) and Read Only Memory(ROM). The one and only memory that the CPU can directly access is the main memory at a very high speed.
It is expensive hence storage capacity is less. RAM is volatile(when the power is switched off the content will be erased) in nature but ROM is non volatile(lt is permanent). In ROM a “boot up” program called BIOS(Basic Input Output System) is stored to “boots up” the computer when it switched on. Some ROMs are given below.
- PROM(Programmable ROM) : It is programmed at the time of manufacturing and cannot be erased.
- EPROM (Erasable PROM): It can be erased and can be reprogrammed using special electronic circuit.
- EEPROM (Electrically EPROM) : It can be . erased and rewritten electrically
Cache Memory : The processor is a very high speed memory but comparatively RAM is slower than Processor. So there is a speed mismatch between the RAM and Processor, to resolve this a high speed memory is placed in between these two this memory is called cache memory. Commonly used cache memories are Level(L1) Cache(128 KB), L2(1 MB),L3(8 MB), L4(128MB).
ii) Secondary Storage alias Auxiliary Memory : Because of limited storage capacity of primary memory its need arises. When a user saves a file, it will be stored in this memory hence it is permanent in nature and its capacity is huge. Eg: Hard Disc Drive(HDD), Compact Disc(CD), DVD, Pen Drive, Blu Ray Disc etc.
i) Magnetic storage device: It uses plastic tape or metal/plastic discs coated with magnetic material.
Hard Disk : Instead of flexible or soft disk it uses rigid material hence the name hard disk. Its storage capacity and data transfer rate are high and low access time. These are more lasting and less error prone. The accessing mechanism and storage media are combined together in a single unit and connect to the mother board via cable.
ii) Optical storage device.
Optical Disk : The high power laser uses a concentrated, narrow beam of light, which is focuses and directed with lenses, prisms and mirrors for recording data. This beams burns very very small spots in master disk, which is used for making molds and these molds are used for making copies on plastic disks. A thin layer of aluminium followed by a transparent plastic layer is deposited on it. The holes made by the laser beam are called pits, interpreted as bit 0 and unburned areas are called lands interpreted as bit 1. Lower power laser beam is used to retrieve the data.
DVD(Digital Versatile Disc) : It is similar to CD but its storage capacity is much higher. The capacity of a DVD starts from 4.7 GB
Blu – ray Disc : It is used to read and write High Definition video data as well as to store very huge amount of data. While Cd and DVD uses red laserto read and write but it uses Blue – Violet laser, hence the name Blu ray disc. The blue violet laser has shorter wave length than a red laser so it can pack more data tightly.
iii) Semiconductor storage (Flash memory): It uses EEPROM chips. It is faster and long lasting.
- USB flash drive: It is also called thumb drive or pen drive. Its capacity varfes from 2 GB to 32 GB.
- Flash memory cards: It is used in Camera, Mobile phones, tablets etc to store all types of data.
Question 12.
With the help of a block diagram, explain the functional units of a computer. (March – 2017)
Answer:
Functional units of computer
A computer is not a single unit but it consists of many functional units(intended to perform jobs) such as Input unit,Central Processing Unit(ALU and Control Unit), Storage (Memory) Unit and Output Unit.
- Input Unit : Its aim is to supply data (Alphanumeric, image , audio, video, etc.) to the computer for processing. The Input devices are keyboard, mouse, scanner,mic, camera,etc
- Central Processing Unit (CPU): It is the brain of the computer and consists of three components
- Arithmetic Logic Unit(ALU) – As the name implies it performs all calculations and comparison operations.
- Control Unit(CU) – It controls over all functions of a computer
- Registers – It stores the intermediate results temporarily.
- Storage Unit(Memory Unit): A computer has huge storage capacity. It is used to store data and instructions before starts the processing. Secondly it stores the intermediate results and thirdly it stores information(processed data), that is the final results before send to the output unit(Visual Display Unit, Printer, etc)
Two Types of the storage unit
i. Primary Storage alias Main Memory :
It is further be classified into Two – Random Access Memory(RAM) and Read Only Memory(ROM). The one and only memory that the CPU can directly access is the main memory at a very high speed. It is expensive hence storage capacity is less. RAM is volatile (when the power is switched off the content will be erased) in nature but ROM is non volatile(lt is permanent)
ii. Secondary Storage alias Auxiliary Memory :
Because of limited storage capacity of primary memory its need arises. When a user saves a file, it will be stored in this memory hence it is permanent in nature and its capacity is huge.Eg: Hard Disc Drive(HDD), Compact Disc(CD), DVD, Pen Drive,Blu Ray Disc etc.
4. Output Unit: After processing the data we will get information as result, that will be given to the end user through the output unit in a human readable form. Normally monitor and printer are used.