NEO CONVENT SR. SEC. SCHOOL, PASCHIM VIHAR, DELHI 63 Paper IP, Class XI-C, Unit Test 1 ( ) Answer Key Max. Marks: 40

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1 NEO CONVENT SR. SEC. SCHOOL, PASCHIM VIHAR, DELHI 63 Paper IP, Class XI-C, Unit Test ( ) Answer Key Max. Marks: 40 Q.a) b) c) d) e) f) Ans. What are the major strengths and weaknesses of a computer? What is an operating system? Name any two. What is the role of an interpreter? Which of the following is not hardware : (i) Hard disk (ii) Operating System (iii) Keyboard (iv) CPU (v) Assembler What do you understand by System software? Name any one. How much memory does the following represent in terms of bits: (i) Nibble (ii) GB a) Strengths: Speed, Accuracy, Reliability and Versatility Weakness: Lack in decision making, Zero IQ b) Operating System An operating system is a system software that acts as an interface between the user and the computer. It is a set of system programs that controls and coordinates the operations of computer system. Eg. of operating system are: Windows0, Linux, Unix, Mac OS, Android, ios etc. c) Interpreter It is a language processor that converts a high level language program into machine level language program line by line as well as executes it. If there is any error in the program, translation and execution stops and the error is reported for debugging. The conversion and execution resumes only after the error is rectified. This is a slow process and consumes high memory. d) (ii) Operating system (v) Assembler e) The functions of all the physical components of the computer system are guided by some instructions or program collectively known as system Software. System software controls all internal activities inside a computer system and between all attached components of a computer system. The common examples of system software are: BIOS, Operating System, Device Drivers and Language Processors f) Nibble = 4 Bits

2 GB = *04*04*04*8 bits Q. Write the full forms of the following terms : (i) USB (ii) DVD (iii) LCD (iv) CRT Ans. (i) USB Universal Serial Bus (ii) DVD Digital Versatile Disk / Digital Video Disk (iii) LCD Liquid Crystal Display (iv) CRT Cathode Ray Tube Q3. Write a short note on :. Graphics tablet. Biometric sensors 3. Cookies 4. Social networking 5. IDE 5 Ans. 3. Graphics tablet Graphics Tablet is used to enter data using a stylus. Most commonly it is used to enter digital signatures.. Biometric sensors It is used to recognize individuals based on physical or behavioral traits. Biometric sensors are used to mark attendance of employees/ students in organizations/ institutions. It is also popular as a security device to provide restricted entry for secured areas. 3. Cookies A cookie is a small bit of text or a file that accompanies requests and pages as they go between the web server and the web browser. Cookies help website to store information about visitors, thus some may violate privacy concerns. 4. Social networking Social networking was an initiative to communicate amongst known and unknown users working over network worldwide. it gives a common platform to find people of varied interests and social backgrounds. It creates an extended network by connecting friends of friends and further enabling the empowerment of knowledge and resources. Some of the common social networking sites are: Facebook, Twitter, Hi5, NetLog, Orkut etc. 5. IDE IDE is an application program consisting of different development tools

3 needed for developing an application. An IDE typically consists of two or more of the following tools:. Source code editor. Compiler 3. Debugger 4. GUI builder 5. Build automation tools 6. Code generator Q4. Explain the points of differences between the following using appropriate examples : i. Serial port and parallel port ii. RAM and ROM iii. OCR and OMR iv. Assembler and compiler v. General purpose application software and specific purpose application software vi. Digital signature and digital certificate vii. Design tab and source tab viii. Text field and text area component 8 Ans. 4 i. SERIAL PORT They transfer data serially. i.e. bit at a time. It needs only one wire to transmit 8 bits. They come in form of 9 and 5 pin male connectors Are used to connect devices like mouse and modem. PARALLEL PORT They send or receive a byte (8 bits) at a time. In this the 8 bits are transmitted parallel to each other. They come in the form of 5 pin female connector. Are used to connect devices like printer, scanner, joystick, web camera, speakers, telephone, network connections etc. ii. RAM stand for Random Access Memory where both read and write operation can take place, but this is volatile memory; its contents are lost when power is turned off ROM stands for Read Only Memory where only read operation can take place. This is a non volatile memory. Both RAM and ROM are the parts of primary memory

4 iii. OCR An OCR is used to read characters of special type font that are printed on conventional paper with conventional ink. It also comprises of a logical system that attempts to determine which of the possible characters is being examined. OMR An OMR is used to transcribe marks that are marked with a dark pencil or a pen on a special pre printed form. It doesn t have any logical system. iv. A Compiler converts an HLL program into object program (Machine Lang.) in one go and once the program is error free, it can be executed later whereas an assembler converts an assembly language program to machine language program. v. General purpose Application Software Software that are designed for general day to day applications and uses are called as general purpose application softwares. Eg. word processors Presentation tools Spreadsheet tools Database management system Specific Purpose Application Software Software that are made for performing specific tasks generally used by the institutions, corporate, business houses etc are called as specific purpose application software. Eg. inventory management system Payroll management system Hotel management Reservation system Report card generator vi. Digital Signature A digital signature is a method for providing the authenticity of a message or document or attachment or software sent through . It is used for software distribution, financial transactions and in other cases where forgery and tampering is possible. Digital Certificate A digital certificate is an electronic document which uses a digital signature to bind together a public key or password required for decode and encoded document with an authentic identity such as name of the person or an organization, their phone number or address and so forth. It is used to verify that a public key belongs to an authorized individual or organization.

5 vii. Design Tab The design tab is used to design the form. Source Tab The source tab is used to view java source code viii. Textfield JTextField is a lightweight component that allows the editing of a single line of text Eg. jtextfield.settext( Welcome to Netbeans ); TextArea A JTextArea is a multi-line area that displays plain text. Eg. jtextarea.settext( Welcome to netbeans ); Q5. What do you mean by a bus? What are the different types of buses? Explain. Ans. 5 A bus is a system that transfers data between computer components or between computers. Buses are the collection of wires that transmit binary numbers, one bit per wire. A typical microprocessor communicates with memory and other devices using three buses :. Address bus This is a system of bus which is used to specify the address of a memory location. The width of the bus determines the number of memory locations that can be addressed.. Data bus This system of bus is a medium, which transfers the data from one place to another in a computer system. 3. Control bus This system of bus carries the signal that gives the report about the status of a device. Q6. What are the major functions performed by a computer? Explain with the help of a block diagram. Ans. 6 The major functions performed by the computer are:. It accepts data or instructions by the way of input. It stores the data 3. It processes the data 4. It controls the operations of the computer 5. It gives the result in the form of output

6 In order to carry out the operations mentioned above the computer allocates the task among its various functional units. A computer receives data and instructions through the input devices which get processed in CPU and the result is shown through output devices. The main memory and the secondary memory are used to store the data inside the computer. Q7. Mention any four safety measures one should follow to protect their computer. Ans. 7. Password should be changed regularly.. Password should not be shared. 3. Scan your computer system regularly with antivirus software. 4. Regularly update your antivirus software. 5. Restricted use of removable storage devices, especially USB Pen Drives. 6. Properly configure the filter option 7. Never download any attachment from an unknown sender. 8. Must take backup of computer system regularly. (Any Four) Q8. Define the term firewall in computers. How does a firewall work? Ans. 8 Firewall A firewall is a technique used in a secured computer system or network to block unauthorized access and allow only the authorized user. Firewalls can be implemented in either hardware or software, or a combination of both. It is a device or set of devices or software running on a computer, which is configured to permit or deny computer applications and set of other software based upon a set of rules and other criteria designed by the network administrator. It is normally placed between a protected network (Usually a LAN) and an

7 unprotected network (Usually Internet). All messages leaving or entering the internet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria. Q 9. Explain the usage of the following methods with the help of an example. parseint(). settext() 3. tostring() 3 Ans. 9. parseint() It is used to convert a string to an integer type. int a = integer.parseint(jtextfield.gettext());. settext() This function is used to change the display text of a component (label, text field or button) during run time. jlabel.settext( Hello ); 3. tostring() To convert an integer value to String type. Integer.toString(number); Q0. Write a program to create a calculator which accepts two numbers and returns the value depending upon the operation selected. The program must have an exit button. Ans. 0 private void jbuttonactionperformed(java.awt.event.actionevent evt) { int fn, sn, sub;

8 fn = Integer.parseInt(jTextField.getText()); sn = Integer.parseInt(jTextField.getText()); sub=fn-sn; jtextfield3.settext(""+sub); private void jbuttonactionperformed(java.awt.event.actionevent evt) { int fn, sn, sum; fn = Integer.parseInt(jTextField.getText()); sn = Integer.parseInt(jTextField.getText()); sum=fn+sn; jtextfield3.settext(""+sum); private void jbutton3actionperformed(java.awt.event.actionevent evt) { int fn, sn, div; fn = Integer.parseInt(jTextField.getText()); sn = Integer.parseInt(jTextField.getText()); div=fn/sn; jtextfield3.settext(""+div); private void jbutton4actionperformed(java.awt.event.actionevent evt) { int fn, sn, pro; fn = Integer.parseInt(jTextField.getText()); sn = Integer.parseInt(jTextField.getText()); pro=fn*sn; jtextfield3.settext(""+pro); private void jbutton5actionperformed(java.awt.event.actionevent evt) { System.exit(0); Q. Write a program to calculate the simple interest, where principal, rate and time are entered by the user and simple interest is calculated using the formula S.I.= (P*T*R)/00

9 Ans. private void jbuttonactionperformed(java.awt.event.actionevent evt) { int p,t,r,si; p = Integer.parseInt(jTextField.getText()); t = Integer.parseInt(jTextField.getText()); r = Integer.parseInt(jTextField3.getText()); si=(p*t*r)/00; jtextfield4.settext(""+si); private void jbuttonactionperformed(java.awt.event.actionevent evt) { System.exit(0); Q. Design a GUI desktop application in Java to accept weight in grams in a text field and convert it into kilograms on the click of a button. Display the result in second text field. The application must have an exit button to end the application and appropriate labels. Ans. private void jbuttonactionperformed(java.awt.event.actionevent evt) { float gm, kg; gm = Integer.parseInt(jTextField.getText()); kg=gm/000; jtextfield.settext(""+kg);

10 private void jbuttonactionperformed(java.awt.event.actionevent evt) { System.exit(0); Q 3. Write a Java code to accept age from the user in the text field and display minor for age below 8 and major for the rest in the label control. Ans. 3 private void jbuttonactionperformed(java.awt.event.actionevent evt) { System.exit(0); private void jbuttonactionperformed(java.awt.event.actionevent evt) { int age; age = Integer.parseInt(jTextField.getText());

11 if (age>=8) { jlabel.settext("major"); else { jlabel.settext("minor");