A-level
COMPUTER SCIENCE
Paper 2
Monday 19 June 2023 Morning Time allowed: 2 hours 30 minutes
Materials
For this paper you must have:
• a
... [Show More] calculator.
Instructions
• Use black ink or black ball-point pen.
• Fill in the boxes at the top of this page.
• Answer all questions.
• You must answer the questions in the spaces provided. Do not write outside
the box around each page or on blank pages.
• 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 marks for questions are shown in brackets.
• The maximum mark for this paper is 100.
Advice
• In some questions you are required to indicate your answer by completely
shading a lozenge alongside the appropriate answer as shown.
• 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.
For Examiner’s Use
Question Mark
1
2
3
4
5
6
7
8
9
10
11
12
TOTAL
2
Answer all questions.
0 1 . 1 A sound is sampled and recorded digitally. The sound is sampled at a rate of 48 000
samples per second (Hz) for 3 minutes using a 16-bit sample resolution.
Calculate the size of the digital recording, giving your answer in mebibytes.
Give your answer rounded to 2 decimal places.
You should show your working.
[2 marks]
Answer mebibytes
0 1 . 2 The highest frequency component in a different sound is 15 000 Hz.
What is the minimum sampling rate that should be used when recording this
sound to ensure that all the frequencies in the original waveform are preserved, so
that when the recording is played back the original sound is recreated accurately?
[1 mark]
Answer Hz
Do not write
outside the
box
*02*
IB/G/Jun23/7517/2
3
0 1 . 3 Figure 1 shows part of the process of playing back a sound that has been
sampled. The binary sound data is used to generate an electrical waveform.
Figure 1
A hardware component on a sound card carries out the process shown in Figure 1.
State the name of this component.
[1 mark]
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