CBSE COMPUTER SCIENCE

WORKSHEET : Dictionary & Sorting 1. Define a dictionary. Give an example. 2. Can sequence operations such as slicing and concatenation be applied to dictionaries? Expalin. 3. Why Lists can’t be used as keys in dictionary. 4. W hy is a dictionary termed as an unordered collection of objects? 5. How is del D and del D[] different from one another if D is a dictionary. 6. Identify and correct the error in the following : D1={“a”:1,1:”a”,[1,”a”]:”two”] 7. Predict the output for the following : d1={5:[6,7,8],"a":(1,2,3)} print(d1.keys()) print(d1.values()) 8. Predict the output for the following : mydict={"m":27,"b":43,"p":25,"d":30} valA='' for i in mydict: if i>valA: valA=i valB=mydict[i] print(valA) print(valB) print(30 in mydict) print("b" in mydict) myLst=list(mydict.items()) myLst.sort(reverse=True) print(myLst) print(myLst[-1]) 9. Predict the output for the following : text="abracadabraaabbccrr" counts={} ct=0 lst=[] for word in text: if word not in lst: lst.append(word) counts[word]=0 ct=ct+1 counts[word]=counts[word]+1 print(counts) print(lst) 10. Predict the output: fruit={} L1=['apple','banana','apple'] for index in L1: if index in fruit: fruit[index]+=1 else: fruit[index]=1 print(len(fruit)) print(fruit) a={(1,2):1,(2,3):2} print(a[2,3]) b={'x':1,'y':2,'z':3} print(b['x']) 11. Create a dictionary whose keys are month names and whose values are the number of days in the corresponding months. i. Ask the user to enter a month name and use the dictionary to tell how many days are in the month. ii. Print out all of the keys in alphabetical order. iii. Print out all the month with 31 days. 12. W hat is sorting? Name some sorting techniques. 13. W hy do number-of-comparisons reduce in every successive iteration in bubble sort. 14. W hat is the difference bubble sort and insertion sort. 15. W rite a python code to sort a list of tuple elements in descending order of points using bubble sort. The tuple-elements of the list contain the following information about different players: (PlayerNo, Playername, Points)

WORKSHEET : LIST 1. Give the output of the following code:- list=['p','r','o','b','l','e','m'] list[1:3]=[] print(list) list[2:5]=[] print(list) 2. Give the output of the following code:- l1=[13,18,11,16,13,18,13] print(l1.index(18)) print(l1.count(18)) l1.append(l1.count(13)) print(l1) 3. WAP in python to create a list of natural numbers from 1 to 50 using for loop. 4. WAP in python to take two lists of same size and create a third list of same size with adding elements at the same location of 1st & 2nd list. E.g. if A=[1,2,3], B= [4,5,6], then C[5,7,9]. 5. WAP in Python to accept any ten numbers from the user in a list and display the maximum number along with its position. 6. WAP in Python to calculate &display the factorial of all elements of an integer list. 7. WAP to remove all even numbers from the given list. 8. WAP the print second largest element of the given list. 9. WAP to display cumulative elements of a given list. For eg LIST is [10,20,30,40] Output should be [10, 30,60,100] 10. Predict the output of the following code in python: T1[0]=2 print(T1) 11. Write the output for the following: x = [4, 7, 9, 12, 10] count = 0 for i in x: count= count + 1 print("Total number of elements = ", count) 12. Write the output for the following: A = [6, 2, 7, 9, 1, 3] Sum = 0 Avg = 0 for x in range(len(A)): Sum += A[x]; Avg = Sum//len(A); print("Sum = ",Sum) print("Average = ", Avg) 13. Write the output for the following: x = [] N = eval(input("enter size of list : ")) for i in range(0, N): x.append(eval(input("enter "+ str(i) + " element : "))) print("Numbers in the list are ") print(x) max1 = x[0] for i in range(1, N): if ( x[i] > max1): max1 = x[i] print("Maximum value in the list = ", max1)

1. Create database Loans and table Loan_Accounts. • Create database loans; • Use loans; • Create table Loan_Accounts(AccNo int(2) • Insert into Loan_Accounts values(1, “R.K. Gupta”, 300000, 36, 12.00, ‘2009-07-19’, 3600); • Insert into Loan_Accounts values(2, “S.P. Sharma”, 500000, 48, 10.00, ‘2008-08-22’, 5000); • Insert into Loan_Accounts values(3, “K.P. Jain”, 300000, 36, NULL, ‘2007-03-08’, 3600); • Insert into Loan_Accounts values(4, “M.P. Yadav”, 800000, 60, 10.00, ‘2008-12-06’, 8000); • Insert into Loan_Accounts values(5, “S.P. Sinha”, 200000, 36, 12.50, ‘2010-01-03’, 2250); • Select * from Loan_Accounts; • Select AccNo, cust_name, Loan_amount from Loan_Accounts; • Select * from loan_accounts where instalments<40; • Select AccNo, Loan_Accounts from Loan_Accounts where Start_Date < ‘2009-04-01’; • Select Int_rate from Loan_Accounts where Start_date > ‘2009-04-01’; • Select * from Loan_Accounts where Int_rate is NULL; • Select * from Loan_Accounts where Int_rate is not NULL; • Select count(Instalments) from Loan_Accounts; • Select * from Loan_Accounts where Start_Date > ‘2009-01-01’; • Select Cust_name, Length(Cust_name), Lcase(Cust_name), Ucase(Cust_name), from Loan_accounts where Loan_amount<400000; • Select Left(Cust_name,3), Right(Cust_name,3), Substr(Cust_name,1 ,3), from Loan_accounts where Int_rate>10; • Select Right(Cust_name,3), Substr(Cust_name,5) from Loan_Accounts; • Select Dayname(Start_date) from Loan_Accounts; • Select Round(Int_rate*100/100,2) from Loan_Accounts where Int_rate>10; • Select * from Loan_Accounts where Loan_amount BETWEEN 400000 AND 500000; • Select AccNo, Cust_name, Loan_amount where Cust_name LIKE “%Sharma”; • Select AccNo, Cust_name, Loan_amount where Cust_name LIKE “%a”; • Select AccNo, Cust_name, Loan_amount where Cust_name LIKE “%a%”; • Select AccNo, Cust_name, Loan_amount where Cust_name LIKE “%a_”; • Select * from Loan_Accounts order by Loan_amount; • Select * from Loan_Accounts order by Start_date desc; • Select * from Loan_Accounts order by Loan_amount, Start_Date desc; • Update loan_accounts set Int_rate = 11.50 where Int_rate =11; • Update loan_accounts set Interest=(Loan_Amount*Int_rate*Instalments)/1200; • Delete from accounts where Start_date <2007;

1. Create database Graduate and table Gratitude. • Create database Graduate; • Use Graduate; • Create table Gratitude(No int(5), Name varchar(10), Stipend int(5), Subject varchar(20), Avg int(5), Division int(5)); • Insert into gratitude values(1, “Karan”, 400, “Accounts”, 68, 1); • Insert into gratitude values(2, “Divakar”, 450, “Informa.Practices”, 68, 1); • Insert into gratitude values(2, “Diya”, 300, “English”, 62, 2); • Insert into gratitude values(4, “Arun”, 350, “Accounts”, 63, 1); • Insert into gratitude values(5, “Sabina”, 500, “Mathematics”, 70, 1); • Insert into gratitude values(6, “John”, 400, “English”, 55, 2); • Insert into gratitude values(7, “Robert”, 250, “Accounts”, 64, 1); • Insert into gratitude values(8, “Rubina”, 450, “Mathematics”, 68, 1); • Insert into gratitude values(9, “Vikas”, 500, “Informa.Practices”, 62, 1); • Select name from Gratitude where division = 1 order by name; • Select name, stipend, subject, stipend * 12 “Amount of Annual Amount” from Gratitude; • Select count(*) from Gratitude where Subject=”Accounts” OR “Informa.Practices”; • Select min(Avg) from Gratitude where subject=”Accounts” • Select sum(stipend) from Gratitude where Division =2; • Select Avg(stipend from Gratitude where Avg >5; • Select count(Distinct Subject) from Gratitude;

ACRONY

107 Kbps Kilobits/Kilobytes Per Second 108 LAN Local Area Network 12TH-CBSE COMPUTER SCIENCE, [03-05-2021 15:23] 109 LED Light Emitting Diode CBSE COMPUTER SCIENCE, [12.10.20 13:04] 110 LLL Low Level Language 111 LPT Line Printer 112 MAC Media Access Control 113 MAN Metropolitan Area Network 114 MB Motherboard/ Megabyte 115 MBASIC Microsoft BASIC (Microsoft) 116 MBPS Megabytes Per Second 117 Mbps Megabits Per Second 118 MICR Magnetic Ink Character Recognition 119 MMX Multimedia Extensions 120 MODEM Modulator Demodulator 121 MSCDEX Microsoft Compact Disc Extension 122 MS-DOS Microsoft – Disk Operating System 123 NAT Network Address Translation 124 NTP Network Time Protocol 125 OCR Optical Character Reader 126 OMR Optical Mark Reader 127 OOP Object Oriented Programming 128 OS Operating System 129 P2P Point to Point Protocol 130 PAN Personal Area Network 131 PC Personal Computer 132 PCB Printer Circuit Board 133 PCI Peripheral Component Interconnect 134 PHP Hypertext Preprocessor 135 PIXEL Picture Element 136 PNG Portable Network Graphics 137 PPP Point to Point Protocol 138 PRN Printer 139 PROM Programmable Read Only Memory 140 RAM Random Access Memory 141 RARP Reverse Address Resolution Protocol 142 RDBMS Relational Data Base Management System 143 RIP Routing Information Protocol 144 RISC Reduced Instruction Set Computer 145 ROM Read Only Memory 146 SAM Software Asset Management 147 SAN Storage Area Network 148 SCSI Small Computer System Interface 149 SDRAM Synchronous Dynamic Random Access Memory 150 SFTP Secure File Transfer Protocol 151 SGML Standard Generalized Markup Language 152 SGRAM Synchronous Graphics RAM 153 SIP Session Initiation Protocol 154 SIU Serial Interface Unit 155 SMTP Simple Mail Transfer Protocol 156 SNAP Sub Network Access Protocol 157 SNMP Simple Network Management Protocol 158 SRAM Static Random Access Memory 159 SYSOP System Operator 160 TCP Transmission Control Protocol 161 UI User Interface 162 URL Uniform Resource Locator 163 USB Universal Serial Bus 164 VCD Video Compact Disk 165 VDU Visual Display Unit 166 VIRUS Vital Information Resource Under Siege 167 VRAM Video Random Access Memory 169 VxD Virtual Extended Driver 170 WAN Wide Area Network 171 WAP Wireless Application Protocol 172 WBMP Wireless Bitmap Image 173 WIFI Wireless fidelity 174 WLAN Wireless Local Area Network 175 WML Wireless Markup Language 176 WWW World Wide Web 178 XGA Extended Graphics Array 179 XHTML Extensible Hyper Text Markup Language 180 XMF Extensible Music File 181 XML Extensible Markup Language 182 XMS Extended Memory Specification 183 FORTRAN Formula Translation

12TH-CBSE COMPUTER SCIENCE, [03-05-2021 15:23] CBSE COMPUTER SCIENCE, [12.10.20 13:04] S. No. Computer Abbreviation Full Form 1 AAC Advanced Audio Coding 2 ABR Average Bit Rate 3 ADSL Asymmetric Digital Subscriber Line 4 AGP Advanced Graphics Port 5 AI Artificial Intelligence 6 AIM AOL Instant Messenger 7 ALGOL Algorithmic Language 8 ALU Arithmetic Logic Unit 9 AOL America Online 10 AMD Advanced Micro Devices 11 API Application Program Interface 12 APT Automatically Programmed Tooling 13 ARP Address Resolution Protocol 14 ARPANET Advanced Research Projects Agency Network 15 ARQ Automatic Repeat Request 16 AS Autonomous System 17 ASCII American Standard Code for Information Interchange 18 ASP Active Server Pages 19 ASPI Advanced SCSI Programming Interface 20 ATA Advanced Technology Attachment 21 ATDT Attention Dial Tone 22 AUI Attachment Unit Interface 23 AUTOEXEC Autoexec Automatic Execution file 24 AVI Audio Video Interleave 25 BASIC Beginner’s All-purpose Symbolic Instruction Code 26 BCC Blind Carbon Copy 27 BCD Binary Coded Decimal 28 BCR Bar Code Reader 29 BDSL Broadband DSL 30 BEDO Burst Extended Data Out (RAM) 31 BGP Border Gateway Protocol 32 BHTML Broadcast Hyper Text Markup Language 33 BIOS Basic Input Output System 34 BIPS Billion Instruction Per Second 35 BIU Bus Interface Unit 36 BMP Bitmap 37 BRD Blu-Ray Disc 38 CC Carbon Copy 39 CD Compact Disk 40 CD-R Compact Disk – Recordable 41 CDROM Compact Disk Read Only Memory 42 CDRW Compact Disk Rewritable 43 CD-WO Compact Disk – Write Once 44 CD-XA Compact Disk – Extended Architecture 45 CGI-BIN Common Gateway Interface – Binary (programming for Web forms) 46 CIS CompuServe Information Service 47 CISC Complex Instructions Set Computers 48 CMD Command 49 CMYK Cyan-Magenta-Yellow-Black (color model) 50 CNM Circulatory Network Mode 51 COAX Coaxial Cable (for Ethernet and similar networks) 52 COBOL Common Business Oriented Language 53 COMPUTER Commonly Operated Machine Particularly Used for Trade/Technology, Education, and Research. 54 CPI Clock / Cycle Per Instruction 55 CPU Central Processing Unit 56 CROM Computerized Range of Motion 57 CRT Cathode Ray Tube( standard type computer monitor display 58 CSLIP Compressed Serial Line Interface Protocol (Internet) 59 CSS Cascading Style Sheets 60 CTRL Control (computer keyboard key) 61 CUI Character User Interface 62 DAC Data Acquisition and Control 63 DAT Digital Audio Tape 64 dB Decibel 65 DBMS Data Base Management System 66 DDL Data Definition Language 67 DHTML Dynamics Hyper Text Markup Language 68 DML Data Manipulation Language 69 DNS Domain Name System 70 DOC Data Optimizing Computer 71 Doc Document 72 DOS Disk Operating System 73 DRAM Dynamic Random Access Memory 74 DVD Digital Video/Versatile Disc 75 DVDR Digital Versatile Disk Recordable 76 DVDRW Digital Versatile Disk Rewritable 77 DCE Data Communications Equipment 78 DVI Digital Visual Interface 79 DVR Digital Video Recorder 80 E-Commerce Electronic Commerce 81 EDC Electronic Digital Computer 82 EDI Electronic Data Interchange 83 EDP Electronic Data Processing 84 EEPROM Electronically Erasable Programmable Read Only Memory 85 EFS Encrypted File System 86 EIDE Enhanced Integrated Drive Electronics 87 E-Mail Electronic Mail 88 EPROM Erasable Programmable Read Only Memory 89 EROM Erasable Read Only Memory 90 FDD Floppy Disk Drive 91 GB Giga Byte 92 GDI Graphical Device Interface 93 GUI Graphical User Interface 94 HD Hard Disk 95 HTML Hyper Text Markup Language 96 HTTP Hyper Text Transfer Protocol 97 I/O Input/Output (serial and parallel ports) 98 IC Integrated Circuit 99 IMAP Internet Message Access Protocol 100 INTEL Integrated Electronics 101 IOP Input Output Processor 102 IP Internet Protocol 103 ISDN Integrated Services Digital Network 104 ISP Internet Service Provider 105 IVR Interactive Voice Response 106 KB KILOBYTE

Q62. Name any two common web browser. Ans. Some of the commonly used web browsers are Google Chrome, Internet Explorer, Mozilla Firefox, Opera, etc. Q63. Write the steps to host a website. Ans. Steps to host a website are : 1. Select the web hosting service provider that will provide the web server space. 2. Identify a domain name, which best suits our requirement. 3. Create logins with appropriate rights and note down IP address to manage web space. 4. Upload the files in properly organised folders on the allocated space. 5. Get domain name mapped to the IP address of the web server. Q64. Name an open source web browser. Ans. Mozilla Firefox is an open source web browser. Q65. Write the steps to open Preference and options page in Mozilla Firefox. Ans. Steps are : 1. Open Mozilla Firefox, and on the top right corner of the browser window, click the Menu button. 2. From the drop down button, select Options/settings. 3. The preferences and Options window will be displayed. Q66. Write any four panels which are available in preference and option page of Mozilla Firefox. Ans. Panels available in preference and option page of Mozilla Firefox are : 1. General Panel 2. Home Panel 3. Search Panel 4. Security and Privacy Panel 5. Sync Panel Q67. Define the following term: 1. Add-ons 2. plugins Ans. Add-on is not a complete program and so is used to add only a particular functionality to the browser. An add-on is also referred to as extension in some browsers. Adding the functionality of a sound and graphics card is an example of an add-on. A plug-in is a complete program or may be a third-party software. For example, Flash and Java are plug-ins. A Flash player is required to play a video in the browser. Q68. What is cookie? Ans. A cookie is a text file, containing a string of information, which is transferred by the website to the browser when we browse it. This string of information gets stored in the form of a text file in the browser. Q69. How cookies are helpful? Ans. It helps in customising the information that will be displayed, for example the choice of language for browsing, allowing the user to auto login, remembering the shopping preference, displaying advertisements of one’s interest, etc. Q70. Identify me a. I am a small text file and help in remembering the shopping preference, displaying advertisements of one’s interest, etc. Ans. Cookie *********

Q50. What is Electronic mail? Give two examples of email service provider. Ans. Email is the short form of electronic mail. It is one of the ways of sending and receiving message(s) using the Internet. An email can be sent anytime to any number of recipients at anywhere. Two email service providers are : 1. Google 2. Yahoo Q51. Write any four common facilities available on email. Ans. Four Common facilities available for an email users are : 1. Sending and receiving mail. 2. Sending the copy of mail 3. Forwarding a received email to other user(s) 4. Filtering spam emails Q52. Write a short note on chatting Ans. Chatting or Instant Messaging (IM) over the Internet means communicating to people at different geographic locations in real time through text message(s). It is a forum where multiple people connect to each other, to discuss their common interests. Q53. Give two examples of instant messengers. Ans. Examples of instant messengers are: Skype, Facebook messenger, WhatsApp, Google Hangout etc. Q54. Write short note on VoIP. Ans. Voice over Internet Protocol or VoIP, allows us to have voice call (telephone service) over the Internet, i.e., the voice transmission over a computer network rather than through the regular telephone network. It is also known as Internet Telephony or Broadband Telephony. Q54. Write two advantages of VoIP. Ans. Advantages of VoIP are : 1. These services are either free or very economical, so people use them to save on cost. That is why these days even international calls are being made using VoIP. 2. VoIP call(s) can be received and made using IP phones from any place having Internet access. Q55. Write any one disadvantages of VoIP. Ans. The disadvantage of VoIP is that its call quality is dependent on Internet connection speed. Slow Internet connection will lead to poor quality voice calls. Q56. Anshuman is running a business. He has studied till class 10. He wants to launch a website for his business. He is confused between static and dynamic web page. As a website developer, help him to understand the difference between static and dynamic web page. Ans. A static webpage is one whose content always remains static, i.e., does not change for person to person. A dynamic web page is one in which the content of the web page can be different for different users. They are more complex and thus take more time to load than static web pages. Q57. Define the following terms : 1. Website 2. Webpage 3. Web server Ans. Website : A website (usually referred to as a site in short) is a collection of web pages related through hyperlinks, and saved on a web server. A visitor navigates from one page to another by clicking on hyperlinks. Webpage : A web page (also referred to as a page) is a document on the WWW that is viewed in a web browser. Basic structure of a web page is created using HTML (Hyper Text Markup Language) and CSS. Web Server: A web server is used to store and deliver the contents of a website to clients such as a browser that request it. A web server can be software or hardware. Q58. What is Error-404? Ans. If the server is not able to locate the page, it sends a page containing the error message (Error 404 – page not found) to the client’s browser. Q59. Write a short note on web hosting. Ans. Web hosting is a service that allows us to put a website or a web page onto the Internet, and make it a part of the World Wide Web. Once a website is created, we need to connect it to the Internet so that users across the globe can access. Q60. What is DNS? Ans. The domain name system (DNS) is a service that does the mapping between domain name and IP address. When the address of a website is entered in a browser, the DNS finds out the IP address of the server corresponding to the requested domain name and sends the request to that server. Q61. Define browser. Ans. A browser is a software application that helps us to view the web page(s). In other words, it helps us to view the data or information that is retrieved from various web servers on the Internet.

Q35. What is Star Topology? Ans. A topology in which each communicating device is connected to a central node, like a hub or a switch is called star topology. Q36. Write two advantages and two disadvantages of star topology. Ans. Two advantages of star topology are: 1. Easy to detect fault. 2. Easy to install. Two disadvantages of star topology are: 1. If the central hub/switch fails then the entire network fails. 2. Installation cost is higher than bus/linear topology Q37. What is ring topology? Ans. In ring topology, each node is connected to two other devices, one each on either side. The nodes connected with each other thus form a ring. In a ring topology data can be transmitted in one direction only. Q38. Write two advantages and two disadvantages of ring topology. Ans. Two advantages of ring topology are : 1. Easy to install and expand. 2. No data collision as data transmission is unidirectional. Two disadvantages of ring topology are: 1. More cable is required than bus topology. 2. If one node is down then the entire network fails. Q39. Explain tree topology in brief. Ans. It is a hierarchical topology, in which there are multiple branches and each branch can have one or more basic topologies like star, ring and bus. Such topologies are usually n WANs where multiple LANs are connected. Q40. What is internet? Ans. The Internet is the global network of computing devices including desktop, laptop, servers, tablets, mobile phones as well as peripheral devices such as printers, scanners, etc. Q41. Name any four smart devices/appliances(devices which can be controlled by internet) other than mobile. Ans. Four Smart devices are: 1. AC 2. TV 3. Fan 4. Light Q42. Write any four uses of Internet. Ans. Four uses of internet are : 1. Internet is used to book online tickets. 2. Internet is used to play games. 3. Internet is used for online teaching, 4. Internet is used to search any information. Q43. Write any four services provided by internet. Ans. Four services provided by internet are : 1. The World Wide Web (WWW) 2. Electronic mail (Email) 3. Chat 4. Voice Over Internet Protocol (VoIP) Q44. Write a short note on WWW. Ans. The World Wide Web (WWW) or web in short, is an ocean of information, stored in the form of trillions of interlinked web pages and web resources. The resources on the web can be shared or accessed through the Internet. Q45. Differentiate between URI and URL. Ans. URI — Uniform Resource Identifier or URI is a unique identifier to identify a resource located on the web. URI identifies a resource (hardware or software) either by its location or by its name or by both. URL is Uniform Resource Locator and provides the location and mechanism (protocol) to access the resource. Q46. Identify the domain name, protocol, sub-domain from the following domain. https://www.csiplearninghub.com/class-11-ch-1/mcq Ans. Domain name = www.csiplearninghub.com Sub Domain Name = www Protocol = https Q47. What is Search Engine? Give two examples Ans. A search engine is a website which help users to find specific information on internet. for example google, bing, yahoo etc. Q48. What is http? Ans. The Hyper Text Transfer Protocol is a set of rules which is used to retrieve linked web pages across the web. It’s more secure and advanced version is HTTPS. Q49. Rajlakshmi is a class 12 computer science student. She is confused between ‘web’ and ‘internet’. As a friend of Rajlakshmi, explain her the difference between web and internet. Ans. The Internet as we know is the huge global network of interconnected computers, which may or may not have any file or webpage to share with the world. The web on the other hand is the interlinking of a collection of WebPages on these computers which are accessible over the Internet.

Q18. Cable TV network services is an example of ____________ (LAN/MAN/WAN) Ans. MAN Q19. What do you mean by Network Devices. Give examples Ans. Those devices which are used to communicate between different hardware used in computer network through different transmission media are called network devices. for example Router, Switch, Modem etc. Q20. What is Modem? Ans. Modem stands for ‘MOdulator DEMolulator’. It refers to a device which is used to convert analog signal to digital signal and vice versa. Q21. Define Network Interface Card. Ans. Network Interface Card (NIC) is a network adaptor used to set up a wired network. It acts as an interface between computer and the network. It is a circuit board mounted on the motherboard of a computer. Each NIC has a MAC address, which helps in uniquely identifying the computer on the network. Q22. What is the purpose of repeater in networking. Ans. The purpose of repeater is to regenerate the weakened signal in the network. Q23. What is repeater? Explain in brief. Ans. A repeater is an analog device that works with signals on the cables to which it is connected. The weakened signal is regenerated and put back on the cable by a repeater. Q24. What is hub? Ans. An Ethernet hub is a network device used to connect different devices through wires. Data arriving on any of the lines are sent out on all the others. Q25. Write one limitation of hub. Ans. The limitation of hub is that if data from two devices come at the same time, they will collide. Q26. Why switch is called intelligent hub? Ans. A switch send the data to only desired node instead of sending to all. Q27. Explain the working of switch in brief. Ans. When data arrives, the switch extracts the destination address from the data packet and looks it up in a table to see where to send the packet. Thus it sends signals to only selected devices instead of sending to all. Q28. Write two differences between hub and switch. Ans. Differences are : HUB SWITCH It sends the data to all the connected node It sends the data to only intended node. It do not provide Packet filtering It provide packet filtering Q29. What is router? Ans. A router is a network device that can receive the data, analyse it and transmit it to other networks. A router connects a local area network to the internet. Q30. What do you mean by ISP? Name any two ISP. Ans. ISP stands for Internet Service Provider. It is an organisation that provides services for accessing the Internet. Two ISP’s are : Airtel, Vodafone Idea limited, Jio, BSNL etc. Q31. What is gateway in computer network? Ans. A gateway is a key access point that acts as a “gate” between an organisation’s network and the outside world of the Internet. Q32. Identify the following a. I am a networking device used to connect multiple computers. I sends the data to only intended node. b. I serves as the entry and exit point of a network. c. If a node from one network wants to communicate with a node of a foreign network, it will pass the data packet through me. d. I am a wireless device which provide Wi-Fi access to smartphones and other devices Ans. a. Switch b. Gateway c. Gateway d. Router Q33. What is Topology? Name three topologies. Ans. The arrangement of computers and other peripherals in a network is called its topology. Common network topologies are mesh, ring, bus, star and tree. Q34. What is bus topology? Ans. A bus topology is an arrangement in which all the computers are connected to a single cable. The cable to which the nodes connect is called a “backbone”. Q35. Write two advantages and two disadvantages of bus topology. Ans. Advantages of bus topology are : 1. It is easy to install. 2. It is cost effective as it does not require much cable. 3. Easy to connect or remove devices in this topology. Disadvantages of bus topology are: 1. Difficult to find faulty device. 2. If the main cable damage, then entire network will be down.

COMPUTER NETWORK Q1. Define Network. Give examples of network in our daily life. Ans. A group of two or more similar things or people interconnected with each other is called network. Examples of network in daily life is : 1. Social network 2. Mobile network 3. Network of computers 4. Airlines, railway, banks, hospitals networks Q2. What do you mean by computer network? Ans. A computer network is an interconnection of two or more computers or computing devices. Q3. Write two advantages of computer network. Ans. Two advantages of computer network are : 1. Sharing of Files. 2. Sharing of resources like printer, scanner. 3. Sharing of single internet connection. Q4. Write two disadvantages of computer network. Ans. Two disadvantages of computer network are : 1. Lack of data security. 2. Viruses can spread easily in network due to interconnectivity of computers. 3. Required a skilled person to handle the network. Q5. Write any five components of computer network. Ans. Five components of computer network are: 1. Network Interface Card(NIC) 2. HUB 3. Switch 4. Repeater 5. Router 6. Modem Q6. What do you mean by node in reference to computer network? Ans. A device which is connected in a network and is capable to send, receive or forward information is called node. Q7. Define the following terms 1. Server 2. Client Ans. Server : It is a special computer which provide services to other computer/devices in a called clients. Clients : A computer/device connected in a network sending request to server is called client. Q8. What do you mean by Client-Server architecture? Ans. In a client – server architecture, the client computer sends a request (regarding data/services) to server and the server accept, process and provide the requested data/services to the client. Example of client – server architecture is Email, WWW etc. Q9. How data is transferred from one computer to another in a network? Ans. Data in a network is divided into smaller chunks called packets. These packets are then carried over a network. Q10. Name the different types of network on the basis of geographical area. Ans. Different types of network on the basis of geographical area are : 1. LAN (Local Area Network) 2. MAN (Metropolitan Area Network) 3. WAN (Wide Area Network) Q11. Write three differences between LAN, MAN and WAN. Ans. Differences are : LAN MAN WAN Local Area Network Metropolitan Area Network Wide Area Network Data transfer rate is high Data transfer rate is average Data transfer rate is low Easy to design and maintain Little bit difficult to design and maintain Difficult to design and maintain A network in school, Hotel, Hospital etc A network in a city. A network in a country. Q12. Name the three cables used in networking. Ans. Three cables used in networking are : 1. Coaxial Cable 2. Twisted Pair Cable 3. Optical Fiber Cable Q13. What do you mean by LAN. Explain in brief. Ans. It is a network that connects computers, mobile phones, tablet, mouse, printer, etc., placed at a limited distance. The geographical area covered by a LAN can range from a single room, a floor, an office having one or more buildings in the same premise. Q14. Aman wants to connect 5 computers placed at different locations in a school. Name the network formed in the school. Ans. LAN Q15. What do you mean by MAN? Explain in brief. Ans. Metropolitan Area Network (MAN) is an extended form of LAN which covers a larger geographical area like a city or a town. Data transfer rate in MAN is considerably less as compared to LAN. Cable TV network or cable based broadband internet services are examples of MAN. Q16. Explain WAN in brief. Ans. Wide Area Network (WAN) connects computers and others LANs and MANs, which are spread across different locations of a country or in different countries or continents. A WAN could be formed by connecting a LAN to other LANs via wired or wireless media. Q17. Name the largest WAN that connects billions of computers, smartphones. Ans. Internet