2025 GCSE (9–1) Computer Science J277/01 Computer Systems (Verified Question Paper With Mark Scheme Combined June 2025)

Monday 12 May 2025 – Afternoon GCSE (9–1) Computer Science J277/01 Computer Systems Time allowed: 1 hour 30 minutes (Verified Question Paper With Mark Scheme Combined June 2025) INSTRUCTIONS •Use black ink. You can use an HB pencil, but only for graphs and diagrams. •Write your answer to each question in the space provided. If you need extra space use the lined pages at the end of this booklet. The question numbers must be clearly shown. •Answer all the questions. INFORMATION •The total mark for this paper is 80. •The marks for each question are shown in brackets [ ]. •Quality of extended response will be assessed in question marked with an asterisk (*). •This document has 16 pages. ADVICE •Read each question carefully before you start your answer. © OCR 2025 [601/8355/X] DC (ST) 336001/5 OCR is an exempt Charity Turn over 1 A student is creating a presentation containing images and sound. (a)One of the files is an audio recording. Complete the description of how a computer stores sound. Fill in the gaps using the given list of terms. Not all terms will be used. analogue colour depth higher repeated smaller binary digital lower sample rate unique bit depth height measuring sampling byte hertz recording seconds An sound wave needs to be converted into a digital sound wave. Sound is when the amplitude of the sound wave is measured at set intervals. The is the number of times a second the sound wave is measured. This is given in Hertz. Each amplitude is given a binary number. The number of bits allocated to each sample is the ..................................................................... . The the number of bits, the wider the number of amplitudes can be measured. [6] (b)The student creates 10 bitmap images using a computer. Each image has a colour depth of 8-bits and a resolution of 800 × 500 pixels. (i)Define the term pixel. .......................................................................................................................................................... . [1] (ii)Calculate the total file size of the 10 images in kilobytes. Show your working out. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... File size: kilobytes [2] (iii)State the minimum number of bits that will be needed to represent 240 different colours. . [1] (c)The student wants to use a secondary storage device to move their files to their home computer. Identify whether the student should use an optical or solid-state type of secondary storage device. Justify your choice. Optical or solid-state ........................................................... Justification ...................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... . [4] 2 A computer has an operating system. (a)Tick () one box on each row to identify the operating system function that will manage each task. Operating system function Memory management Peripheral management User management File management Multitasking Renaming a folder Creation of user accounts Installation of a printer driver Transfer of data to and from RAM [5] (b)A computer also has utility software. (i)State the purpose of utility software in a computer. .......................................................................................................................................................... . [1] (ii)Explain the purpose and function of encryption software. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .