2023 AQA GCSE COMPUTER SCIENCE 8525/2 Paper 2 Computing concepts Question Paper & Mark scheme (Merged) June 2023 [VERIFIED] GCSE COMPUTER SCIENCE

2023 AQA GCSE COMPUTER SCIENCE 8525/2 Paper 2 Computing concepts Question Paper & Mark scheme (Merged) June 2023 [VERIFIED] GCSE COMPUTER SCIENCE Paper 2 Computing concepts Thursday 25 May 2023 Afternoon Time allowed: 1 hour 45 minutes Materials • There are no additional materials required for this paper. • You must not use a calculator. Instructions • Use black ink or black ball-point pen. Use pencil only for drawing. • Answer all questions. • You must answer the questions in the spaces provided. • If you need extra space for your answer(s), use the lined pages at the end of this book. Write the question number against your answer(s). • Do all rough work in this book. Cross through any work you do not want to be marked. Information • The total number of marks available for this paper is 90. Advice For Examiner’s Use Question Mark 1–6 7 8 9–10 11 12 13 14 15 16 TOTAL For the multiple-choice questions, completely fill in the lozenge alongside the appropriate answer. CORRECT METHOD WRONG METHODS If you want to change your answer you must cross out your original answer as shown. If you wish to return to an answer previously crossed out, ring the answer you now wish to select as shown. *JUN* IB/G/Jun23/E12 8525/2 2 Answer all questions in the spaces provided. 0 1 . 1 The number base 2 is called binary. Shade one lozenge to show which number base is called hexadecimal. [1 mark] A 6 B 8 C 10 D 16 0 1 . 2 Shade two lozenges to show the statements that are true about hexadecimal. [2 marks] A Hexadecimal can represent a greater range of numbers than binary. B Hexadecimal is easier for people to read than binary. C Hexadecimal is faster for a computer to process than binary. D Hexadecimal is more accurate than binary. E Hexadecimal takes less space in RAM than binary. F Hexadecimal takes less time to type than binary. 0 2 . 1 Convert the decimal number 171 into binary. [1 mark] Do not write outside the box *02* IB/G/Jun23/8525/2 3 0 2 . 2 Convert the hexadecimal number 2D into binary. You should show your working. [2 marks] Answer 0 3Add together the following three binary numbers and give your answer in binary. [2 marks] + 0 4Convert bits to megabytes (MB). You should show your working. [2 marks] Answer MB Do not write outside the box Turn over ► *03* IB/G/Jun23/8525/2 4 0 5Describe the binary shift that would be used to divide a binary number by four. [1 mark] 0 6 . 1 When a sound wave is converted to a digital form it is sampled. The sampling rate is measured in hertz (Hz). Define the term hertz. [1 mark] 0 6 . 2 A sampling rate of 20 000 Hz and a sample resolution of four bits is used to make a digital recording of a sound that lasts 50 seconds. What is the minimum file size of the recording in megabytes (MB)? You should show your working. [3 marks] Answer MB Do not write outside the box 15 *04* IB/G/Jun23/8525/2 5 Turn over for the next question DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED Do not write outside the box Turn over ► *05* IB/G/Jun23/8525/2 6 0 7 . 1 The term pixel is short for Picture Element. Define the term pixel. [1 mark] 0 7 . 2 Figure 1 shows a 5 pixel x 5 pixel image. A minimum colour depth of two bits is needed to store the image. Figure 1 Explain how the image in Figure 1 can be represented as a bitmap. [3 marks] Do not write outside the box *06* IB/G/Jun23/8525/2 7 0 7 . 3 A 10 pixel x 10 pixel image contains five different colours. Calculate the minimum file size, in bits, of this image when represented as a bitmap. You should show your working.