Kerala Plus Two Computer Science Model Question Paper 2
Time: 2 Hours
Cool off time : 15 Minutes
General Instructions to candidates:
- There is a ‘cool off time’ of 15 minutes in addition to the writing time of 2 hrs.
- Your are not allowed to write your answers nor to discuss anything with others during the ‘cool off time’.
- Use the ‘cool off time’ to get familiar with the questions and to plan your answers.
- Read questions carefully before you answering.
- All questions are compulsory and only internal choice is allowed.
- When you select a question, all the sub-questions must be answered from the same question itself.
- Calculations, figures and graphs should be shown in the answer sheet itself.
- Malayalam version of the questions is also provided.
- Give equations wherever necessary.
- Electronic devices except non programmable calculators are not allowed in the Examination Hall.
Answer all questions from 1 to 5 (5×1 = 5)
Question 1.
The variables declared inside the class are known as ……….
Question 2.
Queue follows the……principle.
Question 3.
A link to a particular section of the same document is called………..
Question 4.
The keyword used to declare a variable in JavaScript is………..
Question 5.
Name a protocol that provides secure file transfer.
Answer any nine questions from 6 to 16 (9×2 = 18)
Question 6.
Orphaned memory blocks are undesirable. How can they be avoided ?
Question 7.
“Structure is a user-defined data type”. Justify this statement.
Question 8.
How does stack overflow and underflow occur?
Question 9.
What is the role of payment gateway in online purchases?
Question 10.
Write two different uses of “+” operator in JavaScript ?
Question 11.
What are the advantages of writing JavaScript code in the head section of an HTML page?
Question 12.
What happens when we use DELETE FROM command without a WHERE clause?
Question 13.
What are the features of AUTO_ INCREMENT constraint?
Question 14.
Write a PHP program to display the perfect numbers below 100.
Question 15.
Why is cyber law important ?
Question 16.
List some uses of biometrics.
Answer any nine questions from 17 to 27 (9×3 = 27)
Question 17.
What are the advantages of character pointer over character array?
Question 18. How C++ implements encapsulation and data hiding?
Question 19.
Write a procedure to implement traversal operation in a linked list.
Question 20.
Create a table with 5 types of fruit names, use headings as serial number, name and cost.
Question 21.
Discuss about six built in functions used in JavaScript.
Question 22.
Categorize the cloud service models.
Question 23.
Using the instance of the EMPLOYEE relation given below, write the result of the following relational algebra expressions.
Question 24.
Explain about the components of SQL.
Question 25.
What is the use of $_SERVER? $_SERVER
Question 26.
Define the following cyber crimes:
a. Cyber terrorism
b. Website defacement
c. Attacks against e-governance web-sites
Question 27.
Explain how cloud service models change the way we use computers
Answer any two questions from 28 to 30 (2 x 5 = 10)
Question 28.
Explain about column constraints.
Question 29.
How can we connect a website hosted in a Webserver to a domain name?
Question 30.
Create a form that accepts information regarding a student. Fields necessary are name, age, class, sex, roll number, hobbies and date of birth. Use appropriate form controls.
Answers
Answer 1.
data member
Answer 2.
FIFO (First In First Out)
Answer 3.
Internal linking
Answer 4.
var
Answer 5.
FTP (File Transfer Protocol)
Answer 6.
If the memory allocated using new operator is not freed using delete, that memory is said to be an orphaned memory block -a block of memory that is left unused, but not released for further allocation. Remedy for memory leak is to ensure that the memory allocated through new is properly deallocated through delete. Memory leak takes place only in the case of dynamic memory allocation. But in case of static memory allocation, the operating system takes the responsibility of allocation and deallocation without user’s instruction. So there is no chance of memory leak in static memory allocation.
Answer 7.
C++ provides facility to define new data types by which such aggregate or grouped data can be represented. The data types defined by user to represent data of aggregate nature are generally known as user-defined data types. Structure is a user-defined data type which represents a collection of logically related data items. It can represent a group of different types .of data under a common name.
Answer 8.
Once the stack is full, and if we attempt to insert an item, an impossible situation arises. This is known as stack overflow.
If the stack is empty and we try to delete an item from the stack, an unfavorable situation arises. This is known as stack underflow.
Answer 9.
Payment gateway is a server that acts as a bridge between merchant server and bank server and transfers money in an encrypted format whenever an online payment/money transfer is made.
Answer 10.
Operator + is used to add two strings. Adding two string means concatenating two strings. If the operands are numbers, it will add the numbers. If the operands are strings it will concatenate the strings. If + operator sees any one operand as string, it will treat both the operands as string type and concatenate the strings.
Answer 11.
It is a visual practice to include scripts in the head section of the web page. The main reason for this is that the body section of most of the HTML pages contains a large volume of text that specifies the contents to be displayed on the web page. Mixing a function definition also with this will create a lot of confusion for the web designer for making any kind of modification in the page. Moreover, the head section of a web page is loaded before the body section. Therefore, if any function call is made in the body section, the function will be executed as the function will be executed as the function definition is already loaded in the memory.
Answer 12.
The rows which are to be deleted are selected by using the WHERE clause. If the WHERE clause is not used, all the rows in the table will be deleted.
Answer 13.
It performs an auto-increment feature. By default, the starting value for this constraint is 1 and will be incremented by 1 for each new record. Only one AUTO_INCREMENT column per table is allowed.
Answer 14.
<?
function is_perfect($number)
{
for ($n = 2; $n <= sqrt($number); $n++)
{
if (!($number % $n))
{
$d += $n;
if ($n <> $number / $n)
$d += $number / $n;
}}
return ++$d == $number;
}
for ($n = 1; $n < 100; $n++)
if (is_perfect($n))
echo $n . '<br />';
?>
Answer 15.
Cyber law is important because it touches almost all aspects of transactions and activities using internet. Whether we realist it or not, every action and every reaction in cyberspace has some legal perspectives.
Answer 16.
Biometrics authentication is used in identification of individual. Biometrics identifiers are the distinctive, measurable characteristics used to label and describe individuals.
Biometric identification is popularly used in attendance management system authentication in computers and other devices, Adhar cards, etc.
Answer 17.
1. Since there is no size specification, a string of any number of characters can be stored. There is no wastage or insufficiency of memory space. But it should be done with initialization, (e.g., char *str = “Program”;)
2. Assignment operator (=) can be used to copy strings.
3. Any character in the string can be referenced using the concept of pointer arithmetic which makes access faster.
4. Array of strings can be managed with optimal use of memory space.
Answer 18.
C++ implements encapsulation and data hiding through the declaration of a class. A class can contain private, protected and public members.
Private: By default, all items defined in a class are private. Members declared under private section are not visible outside the class.
Protected: Members declared as protected are visible to its derived class, but not outside the class.
Public: All variables or functions defined after the public access specifier are accessible anywhere in our program.
Answer 19.
In linked list, traversal begin from the first node. The pointer Start gives the address of the first node, so that we can access the data part using arrow (->) operator. Then we access the link part of the first part, which is the address of the second node. Using this address, we can access the data and link of the second node. This process is continued until we found NULL pointer in the link of a node.
Answer 20.
<HTML> <HEAD> <TITLE> Fruits Details </ TITLE> </HEAD> <BODY> <TABLE Border = “1”> <TR> <TH> Serial number </TH> <TH>Name </TH> <TH>Cost</TH> </TR> <TR> <TD>1</TD> <TD>Mango</TD> <TD>70</TD> </TR> <TR> <TD>2</TD> <TD > Apple < /TD > <TD>100</TD> </TR> <TR> <TD>3</TD> <TD>Orange</TD> <TD>40</TD> </TR> <TR> <TD>4</TD> <TD>Grapes</TD> <TD>90</TD> </TR> <TR> <TD>5</TD> <TD>Plum</TD> <TD>150</TD> </TR> </BODY> </HTML>
Answer 21.
- alert() function: This function is used to display a message on the screen. This function is used to display a message to the user at the time of data validation, eg., alert (“Welcome to JavaScript”);
- isNaN() function: This function is used to check whether a value is a number or not. In this function, NaN stands for Not a Number. The function returns true if the given value is not a number, eg., isNaN(“Abc”);
- toUpperCasef) function: This function returns the upper case form of the given string. It is called along with the name of the string variable.
eg., x.toUpperCaseO; returns the upper case form of the string in the variable x. - toLowerCaseO function: It returns the lower case form of the given string. If all the characters in the string are already in the, lower case, the toLowerCase () returns the same string.
eg., var x, y;
x = “Anuvritha”;
y = x.toLowerCase ();
alert(y); - charAt() function: It returns the character at a particular position. charAt(0) returns the first character in the string. charAt(1) returns the second character in the string and so on.
eg., var x, y;
x = “Orange”;
y = x.charAt(2);
alert(y);
This will display character ‘a’. - length property: It returns the length of the string, length means, the number of characters in the string. The property is called along with the variable.
eg., var x, y;
x = “Orange”;
y = x.length;
alert(y);
Answer 22.
Software as ab Service (SaaS): It gives subscribers access to both resources and applications. Here a complete application is offered to the customer, as a service on demand. Consumers purchase the ability to access and use and an application or service that is hosted in the cloud.
Platform as a Service (PaaS): A PaaS system goes a level above the software as a Service setup. A PaaS provider gives subscribers access to the components that they require to develop and operate applications over the internet. The customer has the freedom to build his own applications, which run on the provider’s infrastructure.
Infrastructure as a Service (IaaS): In this, as the name states, deals primarily with computational infrastructure. IaaS provides basic storage and computing capabilities as standardized services over the network. The customer would typically set up his own software on the infrastructure.
Answer 23.
Answer 24.
1. Data Definition Language (DDL): These are used to create, modify and remove database objects.
2. Data Manipulation Language (DML): It provides commands for data manipulations. DML is a component of SQL that enhances efficient user interaction with the data system by providing a set of commands.
3. Data Control Language (DCL): It is used to control access to the database, which is very essential to a database system with respect to security concerns.
Answer 25.
It holds information about headers, script locations etc. Its elements are:
$_SERVER [‘PHP_SELF’] - returns the file name of the currently executing script. $_SERVER [‘SERVER_NAME’] - re-turns the name of the host server. $_SERVER [‘SCRIPT_NAME’] - Same as $_SERVER [‘PHP_SELF’]
Answer 26.
a. It is a cyber attack against sensitive computer networks like nuclear power plants, air traffic controls, gas line controls, telecom, etc. These types of attacks against governments are increasing globally. Cyber terrorism focuses on the use of the internet by anti-nationals to affect a nation’s economic and technological infrastructure. It may prove to be very costly to a country. Therefore governments provide very powerful security mechanisms for their servers.
b. This is a common cyber attack against a government. Defacement of websites includes hacking of government websites and posting derogatory comments about a government in those websites.
c. These types of attacks deny a particular online government service. This is done using a Distributed Denial of Service (DDoS) attack. They gain access to website administration through content management system and destroy the data. This causes huge loss to the government.
Answer 27.
Software as ab Service (SaaS): It gives subscribers access to both resources and applications. Here a complete application is offered to the customer, as a service on demand. Consumers purchase the ability to access and use and an application or service that is hosted in the cloud.
Platform as a Service (PaaS): A PaaS system goes a level above the software as a Service setup. A PaaS provider gives subscribers access to the components that they require to develop and operate applications over the internet. The customer has the freedom to build , his own applications, which run on the provider’s infrastructure.
Infrastructure as a Service (IaaS): In this, as the name states, deals primarily with computational infrastructure. IaaS provides basic storage and computing capabilities as standardized services over the network. The customer would typically set up his own software on the infrastructure.
Answer 28.
These are applied only to individual columns. They are written immediately after the data type of the column. They are:
- NOT NULL: It specifies that a column can never have NULL values. NULL is a keyword that represents an empty value.
- Two NULL values cannot be added, subtracted and compared.
- AUTO_INCREMENT: It performs an auto-increment feature. By default, the starting value for this constraint is 1 and will be incremented by 1 for each new record. Only one AUTO_ INCRE-MENT column per table is allowed.
- UNIQUE: It ensures that no two rows have the same value in the column specified with the constraint.
- PRIMARY KEY: It declares a column as the primary key of the table. It is similar to UNIQUE except that it can be applied only to one column or combination of columns. The primary keys cannot contain NULL values.
- DEFAULT: A default value can be set for a column, in case the user does not provide a value for that column of a record.
Answer 29.
Domain names are used to identify a website in the Internet. After finalizing a suitable domain name for our website, we have to check whether this domain name is available for registration or its is already in use by somebody else. The websites like www.whois .net check the database of ICANN that contain the list of all the registered domain names. If the domain name entered is available, we can proceed with the registration. The registration requires filling information for WHOIS database of domain names for ICANN. WHOIS information requires the name, address, telephone number and e-mail address of the registrant. After paying the annual registration fees online, the domain is purchased and is registered in our name. Our domain name has to be connected to the IP address if the web server where the web pages are stored. This is done using ‘A record’ (Address record) of the domain. An ‘A record’ is used to store the IP address of a web server connected to a domain name. The ‘A record’ can be modified by logging into the control panel of the domain.
Answer 30.
<HTML> <HEAD> < TITLE > Details of Students </TITLE> </HEAD> <FORM name = myform METHOD = post action = “save.php”> <FIELDSET> <LEGEND> Enter Details of student </LEGEND> Name <INPUT TYPE = “text” Name = txtname> <BR> Age<INPUT TYPE = “text” Name = txtage> <BR> Class<INPUT TYPE = “text” Class= txtclass> <BR> Sex<INPUT TYPE = “radio” Name = sex VALUE = Male> Male <INPUT Type = “radio” Name = sex VALUE = Female> Female <BR> Hobbies <INPUT Type = “checkbox” Name = chkGarden > Gardening <INPUT Type = “checkbox” Name = chkRead> Reading <BR> < INPUT Type =“Submit” Value= “Save”> <INPUT Type=“Reset”Value= “Clear”> </FIELDSET> </FORM> </BODY> </HTML>