IGCSE Computer Science 0478 Paper 13, Oct/Nov 2023

Question paper and mark scheme75 marks10 questions

Solve it on ExamPal

Practise

Untimed. Write on the paper and check as you go.

Start

Exam

Timed, with a clock you set, like sitting the real paper.

Start

Opens full screen.

Papers open in

Opening the question paper

Read as textThe questions and the mark scheme as plain text. Easier to read on a phone.

Question paper

0478/13 · Oct/Nov 2023

Download PDF
1

A mobile telephone has built-in input and output devices.

a

Give two examples of an input device that would be built into a mobile telephone.

[2]
b

Give one example of an output device that would be built into a mobile telephone.

[1]
c(i)

The data storage in the mobile telephone can be measured using different units of measurement. State how many bits are equal to a byte.

[1]
c(ii)

State how many kibibytes (KiB) equal a mebibyte (MiB).

[1]
d

The mobile telephone has an operating system. Describe the purpose of the operating system.

[3]
2

Humans use a denary number system and computers use a binary number system.

a

Explain what is meant by a binary number system.

[2]
b

Convert the denary numbers 14, 59 and 234 to binary.

[3]
c

Convert the denary numbers 9, 26 and 65 to hexadecimal.

[3]
d

Convert the positive denary number 123 to 8-bit binary using two’s complement. Show all your working.

[2]
e

Add the binary values 00110011 and 01111000 using binary addition. Give your answer in binary. Show all your working.

[3]
3

A computer has a central processing unit (CPU).

a

Circle three components that are built into the CPU. accumulator (ACC) control unit (CU) graphics card hard disk drive (HDD) motherboard program counter (PC) random access memory (RAM) read only memory (ROM)

[3]
b

The CPU has cache. Explain the purpose of the cache.

[2]
c

The CPU has a component that regulates the number of fetch–decode–execute cycles the CPU can perform in a second. State the name of this component.

[1]
d

The CPU has a component that carries out all calculations and logical operations. State the name of this component.

[1]
4

An employee uses a web browser on their computer.

a

Describe the main purpose of a web browser.

[2]
b

The employee wants his payment details to be automatically filled in when he buys products using the internet. Identify the function of a web browser that could be used for this purpose.

[1]
c

The employee wants to be able to quickly access websites that he regularly uses. Identify the function of a web browser that could be used for this purpose.

[1]
d

The web browser uses the secure socket layer (SSL) protocol to transmit personal data securely over the internet. State how the SSL protocol secures the data for transmission.

[1]
5

Errors can occur when data is transmitted.

a

Give one reason an error may occur when data is transmitted.

[1]
b

Some error detection methods use a calculated value to check for errors. Tick (✓) one box to show which error detection method does not use a calculated value to check for errors. A Check digit B Checksum C Echo check D Parity check

[1]
c

An automatic repeat request (ARQ) can be used to make sure that data is received free of errors. It can use a positive or negative acknowledgement method to do this. Explain how an ARQ operates using a positive acknowledgement method.

[5]
6

A company uses cloud storage to store its data.

a

Tick (✓) one box to show which is not a characteristic of cloud storage. A Data is accessed through a network B Data is stored locally C Data is stored remotely D Physical servers are used to store the data

[1]
b

Explain two advantages for the owners of the company of storing its data in cloud storage.

[4]
c

Explain one disadvantage to employees of the company storing data in the cloud.

[2]
7

A photographer takes an image with a digital camera. The photographer sets the resolution and colour depth for the image.

a

State what is meant by the image resolution.

[1]
b

State what is meant by the image colour depth.

[1]
c

Give one benefit of increasing the colour depth of the image.

[1]
d

The photographer compresses the image using a method that permanently reduces the colour depth and resolution of the image. Identify which compression method the photographer uses.

[1]
e

One benefit for compressing the image is to reduce the storage space it uses. Give two other benefits of compressing the image.

[2]
8

Draw and annotate a diagram to represent the role of a router.

[4]
9

A computer has secondary storage.

a

The table contains statements about secondary storage. Complete the table by writing the type of secondary storage that applies to each statement. Some types of secondary storage may apply to more than one statement.

Type of secondary storageStatement
data is stored using pits and lands
data is stored using control gates and floating gates
data is stored using electromagnets
data is stored using a laser
data is stored on a platter that is divided into tracks and sectors
[5]
b

Explain two differences between primary storage and secondary storage.

[4]
10

A car repair garage uses an expert system.

a

Complete the description about the operation of the expert system. Use the terms from the list. Some of the terms in the list will not be used. inference engine interface knowledge base machine learning mechanical engine output device question base rule base An expert system has a ....................................................... that contains a list of facts. The ....................................................... applies the ....................................................... to the ....................................................... to reach a diagnosis for the repair of the car. The user provides data to the system using an ....................................................... .

[5]
b

The expert system has machine learning capabilities. Describe what is meant by machine learning capabilities.

[4]

Mark scheme

0478/13 · Oct/Nov 2023

Download PDF

1a · 2 marks

  • 1 mark

    Touchscreen // Microphone // Keyboard // Keypad // Digital camera // Sensor // by example // Biometric device // Button

  • 1 mark

    Touchscreen // Microphone // Keyboard // Keypad // Digital camera // Sensor // by example // Biometric device // Button

1b · 1 mark

  • 1 mark

    Screen // Speaker // LED/Light // Actuator/Motor

1c(i) · 1 mark

  • 1 mark

    8

1c(ii) · 1 mark

  • 1 mark

    1024

1d · 3 marks

  • 1 mark

    It performs the basic functions of a computer

  • 1 mark

    It manages the hardware

  • 1 mark

    It provides a platform to run software // It provides a user interface // It performs tasks such as (any example of function of an operating system)

2a · 2 marks

  • 1 mark

    It has a base of 2

  • 1 mark

    It only uses two values // … that are 1 and 0

2b · 3 marks

  • 1 mark

    (0000)1110

  • 1 mark

    (00)111011

  • 1 mark

    11101010

2c · 3 marks

  • 1 mark

    9

  • 1 mark

    1A

  • 1 mark

    41

2d · 2 marks

  • 1 mark

    One mark for suitable working method e.g. conversion to binary

  • 1 mark

    01111011

2e · 3 marks

  • 1 mark

    First correct nibble: 1010

  • 1 mark

    Second correct nibble: 1011

  • 1 mark

    Correct working e.g. correct carries

3a · 3 marks

  • 1 mark

    Accumulator (ACC)

  • 1 mark

    Control unit (CU)

  • 1 mark

    Program counter (PC)

3b · 2 marks

  • 1 mark

    It is a type of storage // …that stores frequently used data/instructions

  • 1 mark

    To speed up access // … as it is faster to access than RAM // It has different levels e.g. L1 – L3

3c · 1 mark

  • 1 mark

    Clock

3d · 1 mark

  • 1 mark

    Arithmetic logic unit // ALU

4a · 2 marks

  • 1 mark

    Display web pages

  • 1 mark

    … by rendering HTML

4b · 1 mark

  • 1 mark

    Storing cookies

4c · 1 mark

  • 1 mark

    Storing bookmarks // Storing favourites

4d · 1 mark

  • 1 mark

    It encrypts it // Uses digital certificates

5a · 1 mark

  • 1 mark

    Interference // crosstalk

5b · 1 mark

  • 1 mark

    C

5c · 5 marks

  • 1 mark

    Timer is started when sending device transmits a data packet to receiver

  • 1 mark

    Receiving device checks the data packet for errors

  • 1 mark

    Once the receiving device knows the packet is error free it sends an acknowledgement back to the sending device …

  • 1 mark

    … and the next packet is sent // If the sending device does not receive an acknowledgement before the timer ends …

  • 1 mark

    … a timeout occurs // … the data packet is resent … // … until acknowledgement received // until max number of attempts reached

6a · 1 mark

  • 1 mark

    B

6b · 4 marks

  • 1 mark

    The data can be accessed from any location // … meaning that employees can work from anywhere with a connection

  • 1 mark

    The hardware is owned/maintained by a third party // … meaning that the company are not responsible for maintaining // meaning the company aren’t responsible for its security

  • 1 mark

    Can increase the storage needed easily // … without needing to buy new hardware

  • 1 mark

    Do not need to house the hardware needed // … costs can be saved on the space saved for this // Cloud system will back up the data // … meaning the company does not need to do this

6c · 2 marks

  • 1 mark

    Internet connection is needed/needs to be stable … // … and if this is not available/unstable the data cannot be accessed

  • 1 mark

    Employees could be pressured to work outside of hours … // … as they can access the data from any location

7a · 1 mark

  • 1 mark

    The dimensions of an image // Number of pixels wide by number of pixels high

7b · 1 mark

  • 1 mark

    The number of bits used to represent each/a colour

7c · 1 mark

  • 1 mark

    A greater range of colours can be seen/used // Image will be closer to the actual content of the image/real life // The image will have more detail

7d · 1 mark

  • 1 mark

    Lossy

7e · 2 marks

  • 1 mark

    Quicker to transmit/upload/download

  • 1 mark

    Not as much bandwidth needed to transmit file // To fit in limitation of file size on e.g. email

8 · 4 marks

  • 1 mark

    The router examining the packet … // … looks for the packet header // … looking for the IP address of destination

  • 1 mark

    The packet being sent toward its correct destination // … by the fastest route // decides which route it takes

  • 1 mark

    Router is shown connecting devices/networks

  • 1 mark

    Router is shown assigning an IP address to a device

9a · 5 marks

  • 1 mark

    optical (data is stored using pits and lands)

  • 1 mark

    solid-state (data is stored using control gates and floating gates)

  • 1 mark

    magnetic (data is stored using electromagnets)

  • 1 mark

    optical (data is stored using a laser)

  • 1 mark

    magnetic (data is stored on a platter that is divided into tracks and sectors)

9b · 4 marks

  • 1 mark

    Primary storage is directly accessible by the CPU // … whereas secondary storage is not directly accessible by the CPU

  • 1 mark

    Primary storage stores the data that is currently in use/for booting the system // … whereas secondary storage stores user’s files/data/operating system/application software

  • 1 mark

    Primary storage normally has a small capacity // … whereas secondary storage normally has a larger capacity

  • 1 mark

    Some parts of primary storage are volatile // … whereas secondary storage is non volatile // Some parts of primary storage the data cannot be changed // … whereas data in secondary storage can be changed // Primary storage has faster access speeds to data // … whereas secondary storage has slower access speeds to data

10a · 5 marks

  • 1 mark

    Knowledge base

  • 1 mark

    Inference engine

  • 1 mark

    Rule base // knowledge base

  • 1 mark

    Knowledge base // rule base

  • 1 mark

    Interface

10b · 4 marks

  • 1 mark

    It is a form of artificial intelligence

  • 1 mark

    Means it can adapt/change (its own processes) // It can edit its own algorithms // It can edit its own data

  • 1 mark

    It can be trained // … this can be supervised/unsupervised // … meaning it can learn with/without human interaction

  • 1 mark

    Analyses patterns and stores successful/unsuccessful results … // … to influence future decisions // (Supervised) means a user tells the system the input and output // (Unsupervised) means the system is given the input and needs to work out the output

Questions

  1. 1
    Question 18 marks
    Mark scheme ›
  2. 2
    Question 213 marks
    Mark scheme ›
  3. 3
    Question 37 marks
    Mark scheme ›
  4. 4
    Question 45 marks
    Mark scheme ›
  5. 5
    Question 57 marks
    Mark scheme ›
  6. 6
    Question 67 marks
    Mark scheme ›
  7. 7
    Question 76 marks
    Mark scheme ›
  8. 8
    Question 84 marks
    Mark scheme ›
  9. 9
    Question 99 marks
    Mark scheme ›
  10. 10
    Question 109 marks
    Mark scheme ›

More 0478 papers

Other papers from Oct/Nov 2023

Solve it on ExamPalStart