The City School Comprehensive Paper 2019-2020 Class 9 CANDIDATE NAME INDEX NUMBER Date: ______________ COMPUTER SCIENCE 2210/11 Theory 1 hour 45 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your School Name, Roll Number and Date in the spaces provided. Write in dark blue or black pen. You may use a pencil for any diagrams, graphs or rough working. Do not use paper clips, glue or correction fluid. Calculators must not be used this paper. Answer all questions. No marks will be awarded for using brand names of software packages or hardware. At the end of examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. The maximum number of marks is 75. This document consists of 09 printed pages. The City School / Comprehensive Paper 2019-20 / Computer Science / Class 9 Page 1 of 9 1 Data files are stored in different file formats. Complete the table by providing a suitable file format for each file type. The first one has been done for you. File Type File Format Pictures .JPEG Text Sound Video [3] 2 Steffi has a number of files of different sizes that contain her work. Tick to show whether each statement is true or false. Statement True False 475KB is larger than 10MB. 250bytes is smaller than 0.5MB. 50GB is larger than 100MB. 1TB is smaller than 4GB. [4] 3 For each of the following groups of hardware items, write down a computer application that would need those items. List of hardware items Application Webcam, microphone, speakers Barcode reader, POS terminal Pressure sensor, ADC, lights, siren Light pen, plotter, 3D printer [4] The City School / Comprehensive Paper 2019-20 / Computer Science / Class 9 Page 2 of 9 4 A security system records footage. One minute of video requires 180 MB of storage. The recording system can store several hours of video footage. Calculate how much storage would be needed for 2 hours of video footage. Show your working and give the answer in Gigabytes (GB). ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ [2] 5 MP3 file compression reduces the size of a music file by 90%. A music track is 80 MB in size. Calculate the file size after compression. How many MP3 files of the size calculated above could be stored on an 800 MB CD? ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ [2] 6 a) A computer has 2048 MB of RAM. How many GBs of RAM does the computer have? Show your working. ________________________________________________________________________ ________________________________________________________________________ [2] b) Describe one item that is stored in RAM. ________________________________________________________________________ ________________________________________________________________________ [2] c) Explain three ways that RAM is different to ROM. 1. ________________________________________________________________________ 2. ________________________________________________________________________ 3. ________________________________________________________________________ [3] The City School / Comprehensive Paper 2019-20 / Computer Science / Class 9 Page 3 of 9 7 Write computer term against each of the description given below. Description Computer Term Reduction of file size by permanently removing some redundant information from the file The file is reduced in size for transmission and storage; it is then put back together again later producing a file identical to the original Data can be read but not altered Stores data currently in use Optical storage media that uses concentric tracks allowing writing and reading to take place at the same time Device that stores data by controlling the movement of electrons within a microchip; there are no moving parts. Optical storage media that uses a single spiral track and uses dual layer technology, allowing high data storage capacity Optical storage media that allows very high storage capacity by using blue/violet laser technology High quality printing of 30 000 colour booklets per day [9] The City School / Comprehensive Paper 2019-20 / Computer Science / Class 9 Page 4 of 9 8 Optical storage media can be used to store data. Describe how the data is read from a Compact Disc (CD). ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ [4] 9 Storage devices and storage media can be categorised as primary, secondary or off-line. Write primary, secondary or off-line next to each storage device or medium to indicate its mostsuitable category. HDD ……………………………………… RAM ……………………………………… ROM ……………………………………… CD-ROM ……………………………………… SSD ……………………………………… DVD-RAM ……………………………………… [6] 10 An office worker is responsible for communicating with other businesses and managing thecomputer systems in the office. State a sensible use that the office worker could make of; (i) a hard disk, ________________________________________________________________________ [1] (ii) a rewritable CD (CD-RW), ________________________________________________________________________ [1] (iii) a CD-ROM. ________________________________________________________________________ [1] The City School / Comprehensive Paper 2019-20 / Computer Science / Class 9 Page 5 of 9 11 In a school, students can use laptop computers which link to the school’s wireless network. (a) State two advantages to students of using this system rather than desktop computers located in specialist computer laboratories. ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ [2] (b) Give two disadvantages of using laptop computers rather than using desktopcomputers. ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ [2] 12 Describe the purpose of the following a) Input devices ________________________________________________________________________ ________________________________________________________________________ [1] b) Output devices ________________________________________________________________________ ________________________________________________________________________ [1] 14 Explain how data is stored in QR code. ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________[4] The City School / Comprehensive Paper 2019-20 / Computer Science / Class 9 Page 6 of 9 15The steps to print a document using a laser printer are shown in the table below. Put each step in the correct order. The first step has been done for you. Step Order As the printing drum rotates, a laser scans across it; this removes the positive charge in certain areas The printing drum is coated in positively-charged toner; this then sticks to the negatively-charged parts of the printing drum The paper goes through a fuser which melts the toner so it fixes permanently to the paper 1 The printer driver ensures that the data is in a format that the laser printer can understand A negatively-charged sheet of paper is then rolled over the printing drum Data is then sent to the laser printer and stored temporarily in the printer buffer The toner on the printing drum is now transferred to the paper to reproduce the required text and images The printing drum is given a positive charge Negatively charged areas are then produced on the printing drum; these match exactly with the text and images to be printed [8] The City School / Comprehensive Paper 2019-20 / Computer Science / Class 9 Page 7 of 9 16 Alexandra has a new mobile device. It has touch screen that uses capacitive technology. a) Describe how a capacitive touch screen registers Alexandra’s touch. ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________