IGCSE Computer Science 0478 Paper 12, Oct/Nov 2023

Question paper and mark scheme75 marks13 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

0478/12 · Oct/Nov 2023

Download PDF
1

Malware can be used to corrupt data stored on a computer.

a

Tick (✓) one box to show which cyber security threat is not a type of malware. A Phishing B Ransomware C Virus D Worm

[1]
b

Identify one other example of malware than those given in part 1(a).

[1]
c

Identify the type of software that is used to find and remove malware from a computer.

[1]
2

A register stores the binary number: 1 1 1 0 0 0 1 1

a

Give the denary number for the binary number stored in the register. Working space

[1]
b

Give the hexadecimal number for the binary number stored in the register. Working space

[2]
c

A logical left shift of two places is performed on the binary number stored in the register. Complete the binary register to show its contents after this logical left shift.

[1]
d

The negative denary number −99 needs to be stored in the register. Complete the register to show the binary number that would be stored, using two’s complement. Show all your working. Working space Register:

[2]
e

The number 01001100 is added to 11100011 Add the two 8-bit binary numbers, using binary addition. Give your answer in binary. Show all your working.

[4]
3

A user’s computer has a central processing unit (CPU) that has a clock speed of 2GHz. She wants to change it to a CPU that has a clock speed of 3GHz.

a(i)

State what is meant by clock speed.

[1]
a(ii)

Explain the effect this change will have on the performance of the CPU.

[2]
b

The CPU contains a memory address register (MAR). Describe the role of the MAR in the fetch–decode–execute cycle.

[2]
c

The CPU has a list of all the machine code commands it can process. State the name of this list of commands.

[1]
4

A washing machine is an example of an embedded system.

a

Give two characteristics of an embedded system. 1 2

[2]
b

Circle three other examples of an embedded system. freezer laptop personal computer (PC) security light system smartphone vending machine web server

[3]
5

A band is recording their new song. They need to consider the sample rate and sample resolution of their recording.

a

Give one benefit of using a higher sample rate to record the song.

[1]
b

Give one drawback of using a higher sample rate to record the song.

[1]
c

Describe what is meant by sample resolution.

[2]
d

The band wants to compress the sound file, but they do not want any data to be permanently removed. Identify the compression method that should be used.

[1]
6

The table contains descriptions about data transmission methods. Complete the table by identifying which data transmission methods are described.

Data transmission methodDescription
Data is transmitted down a single wire, one bit at a time, in one direction only.
Data is transmitted down multiple wires, multiple bits at a time, in both directions, but only one direction at a time.
Data is transmitted down a single wire, one bit at a time, in both directions at the same time.
Data is transmitted down multiple wires, multiple bits at a time, in one direction only.
[4]
7

A train station has a ticket inspector who checks each customer’s ticket before they are allowed to get on the train. The train station wants a system that will allow the tickets to be automatically checked.

a

Identify two suitable input devices that can be used to automatically read the tickets. 1 2

[2]
b

The train driver pushes a button to close the train door when all passengers have boarded the train. The train door will only close when there are no passengers in the doorway. The system to check there are no passengers in the doorway uses a sensor and a microprocessor. Explain how the sensor and the microprocessor are used to check whether the train door can be closed.

[6]
8
a

Draw and annotate a diagram that demonstrates the cyber security threat of data interception.

[4]
b

Identify one security solution that will help keep data safe from data interception and state why it will help keep the data safe.

[2]
9

The table contains terms and descriptions about the internet. Complete the table with the missing terms and descriptions.

TermDescription
the collective name for all the web pages available
a small text file, stored by the web browser, that can store a user’s personal data
uniform resource locator (URL)
web server
the language used to create a website. Example tags are <head> and <body>
a protocol that is used to request and send web pages
[6]
10

A business has a system that is described as having artificial intelligence (AI).

a

State one of the main characteristics of an AI system.

[1]
b

An AI system is an expert system. Explain how an expert system operates.

[6]
11

A manufacturing company uses an automated system in its manufacturing process.

a

The automated system uses a flow sensor. Identify what a flow sensor measures.

[1]
b

Explain one advantage to employees of using an automated system in manufacturing.

[2]
c

Explain one disadvantage to the company owner of using an automated system in manufacturing.

[2]
12

Digital currency can be used to pay for products and services. Digital currencies are often tracked using digital ledgers.

a

Give two other features of digital currency. 1 2

[2]
b

Identify the process that uses a digital ledger to track the use of digital currency.

[1]
13

Storage and memory are important components of a computer system.

a(i)

Primary storage is one type of storage in a computer system. Tick (✓) one box to show which is an example of primary storage. A compact disk (CD) B hard disk drive (HDD) C random access memory (RAM) D solid-state drive (SSD)

[1]
a(ii)

Give one characteristic of primary storage.

[1]
b

Virtual memory can be created in a computer system. Complete the description about virtual memory. Use the terms from the list. Some of the terms in the list will not be used. Some terms may be used more than once. binary hard disk drive (HDD) hexadecimal operating system pages random access memory (RAM) read only memory (ROM) sectors software tracks virtual memory Virtual memory is used when the ...................................................................... is full. It is created by partitioning the ...................................................................... . Data is divided into ...................................................................... that can be sent from ...................................................................... to the ...................................................................... to be temporarily stored until they are required.

[5]

Mark scheme

0478/12 · Oct/Nov 2023

Download PDF

1a · 1 mark

  • 1 mark

    A

1b · 1 mark

  • 1 mark

    Spyware // Keylogger / Adware / Trojan horse

1c · 1 mark

  • 1 mark

    Anti-malware

2a · 1 mark

  • 1 mark

    227

2b · 2 marks

  • 1 mark

    E

  • 1 mark

    3

2c · 1 mark

  • 1 mark

    1 0 0 0 1 1 0 0

2d · 2 marks

  • 1 mark

    suitable working method e.g. flip and add 1

  • 1 mark

    10011101

2e · 4 marks

  • 1 mark

    Correct nibble 1

  • 1 mark

    Correct nibble 2

  • 1 mark

    Correct working e.g. correct carry

  • 1 mark

    Showing overflow bit

3a(i) · 1 mark

  • 1 mark

    The maximum number of FDE cycles/instructions a CPU can perform/process/execute in a second

3a(ii) · 2 marks

  • 1 mark

    Increases/improves the performance // Tasks can be performed quicker/faster

  • 1 mark

    … because more FDE cycles/instructions can be processed in a second

3b · 2 marks

  • 1 mark

    Stores addresses …

  • 1 mark

    … of next instruction/data to be fetched // where data is to be written to

3c · 1 mark

  • 1 mark

    Instruction set

4a · 2 marks

  • 1 mark

    Performs a single/limited/dedicated function/task / It has a microprocessor / It has dedicated hardware / Uses firmware / It is normally built into a larger device/system / User normally cannot reprogram / It does not require much power / It is cheap to manufacture / Works automatically // works without human intervention / It is small (in size) / It is a real-time system

  • 1 mark

    Second valid point from list

4b · 3 marks

  • 1 mark

    security light system

  • 1 mark

    freezer

  • 1 mark

    vending machine

5a · 1 mark

  • 1 mark

    The recording of the song is more accurate/closer to original

5b · 1 mark

  • 1 mark

    The file size will be increased / The file will require more storage space

5c · 2 marks

  • 1 mark

    The number of bits that are used per sample / … that provides the variation in amplitude that can be stored for each sample // defines the number of different amplitudes that can be recorded / … that determines how quiet/loud the sounds are that can be recorded / Example e.g. 16-bit

  • 1 mark

    Second valid point from list

5d · 1 mark

  • 1 mark

    Lossless

6 · 4 marks

  • 1 mark

    serial simplex: Data is transmitted down a single wire, one bit at a time, in one direction only.

  • 1 mark

    parallel half-duplex: Data is transmitted down multiple wires, multiple bits at a time, in both directions, but only one direction at a time.

  • 1 mark

    serial full-duplex: Data is transmitted down a single wire, one bit at a time, in both directions at the same time.

  • 1 mark

    parallel simplex: Data is transmitted down multiple wires, multiple bits at a time, in one direction only.

7a · 2 marks

  • 1 mark

    Barcode scanner / QR code scanner / Digital camera

  • 1 mark

    Second valid device from list

7b · 6 marks

  • 1 mark

    Proximity/infrared/pressure sensor used

  • 1 mark

    Sensor continually sends digitised data to microprocessor // When driver pushes button, sensor sends digitised data to the microprocessor

  • 1 mark

    Microprocessor compares data to stored value(s)

  • 1 mark

    If in range/out of range/matches, microprocessor sends signal to close the door

  • 1 mark

    Actuator used to close door

  • 1 mark

    If not in range/out of range/does not match door will not close // If not in range/out of range/does not match actuator not activated/signal not sent as passenger in door // If not in range/out of range/does not match a timer is set to check again // If not in range/out of range/does not match a signal is sent to alert the driver/output a message // This process repeats until the door can close

8a · 4 marks

  • 1 mark

    Data is being sent from one device to another

  • 1 mark

    The data is being examined during transmission / Packet sniffer is used

  • 1 mark

    Intercepted data is reported to a third-party during transmission …

  • 1 mark

    … and analysed for anything useful / Connection hacked to spoof destination address

8b · 2 marks

  • 1 mark

    Encryption …

  • 1 mark

    … if the data is intercepted it will be meaningless (because they do not have the decryption key)

9 · 6 marks

  • 1 mark

    world wide web: the collective name for all the web pages available

  • 1 mark

    cookie: a small text file, stored by the web browser, that can store a user’s personal data

  • 1 mark

    uniform resource locator (URL): the text-based address for a website // It is made up of the protocol, domain name and filename/folder name

  • 1 mark

    web server: Stores web pages // receives requests from clients and returns requested web page

  • 1 mark

    hypertext markup language // HTML: the language used to create a website. Example tags are <head> and <body>

  • 1 mark

    hypertext transfer protocol // HTTP: a protocol that is used to request and send web pages

10a · 1 mark

  • 1 mark

    The ability to learn/adapt // machine learning abilities / The collection of data and the rules for using that data / The ability to reason // has problem solving abilities // makes predictions / Simulates intelligent/human behaviour / Analyses patterns

10b · 6 marks

  • 1 mark

    It has an interface …

  • 1 mark

    … used to input data/view output

  • 1 mark

    It has a knowledge base

  • 1 mark

    It has a rule base

  • 1 mark

    It has an inference engine

  • 1 mark

    Applies the rule base to/and the knowledge base to provide output/diagnosis/result/solution/decision / Decides what to ask next based on the data input

11a · 1 mark

  • 1 mark

    Amount of liquid/gas/steam flowing/moving through an environment

11b · 2 marks

  • 1 mark

    Benefit (e.g. Increases safety / Can increase jobs/skills / No need to do repetitive tasks)

  • 1 mark

    Matching description (e.g. …meaning that workers do not need to go into dangerous areas to collect data/make checks/do dangerous tasks / …as employees are needed to learn/maintain the equipment / … so, they can use their time on other/more skilled tasks)

11c · 2 marks

  • 1 mark

    Drawback (e.g. High set-up/installation costs / Utility/maintenance/repair costs / Deskilling of the workforce)

  • 1 mark

    Matching description (e.g. … it would mean the company need to find a lot of money up front to pay for the equipment // employees will need training / … increase in bills such as electricity // skilled employees will be required to maintain the system // equipment will break/need updating / … may mean that workers will no longer have the skills for some of the manufacturing jobs, should the equipment break)

12a · 2 marks

  • 1 mark

    Only exists electronically / Can be a decentralised system / Can be a centralised system / Usually encrypted

  • 1 mark

    Second valid feature from list

12b · 1 mark

  • 1 mark

    Blockchain

13a(i) · 1 mark

  • 1 mark

    C

13a(ii) · 1 mark

  • 1 mark

    Directly accessed by the CPU / Has both volatile and non-volatile storage

13b · 5 marks

  • 1 mark

    Random access memory (RAM)

  • 1 mark

    Hard disk drive (HDD)

  • 1 mark

    Pages

  • 1 mark

    Random access memory (RAM)

  • 1 mark

    Virtual memory // Hard disk drive (HDD)

Questions

  1. 1
    Question 13 marks
    Mark scheme ›
  2. 2
    Question 210 marks
    Mark scheme ›
  3. 3
    Question 36 marks
    Mark scheme ›
  4. 4
    Question 45 marks
    Mark scheme ›
  5. 5
    Question 55 marks
    Mark scheme ›
  6. 6
    Question 64 marks
    Mark scheme ›
  7. 7
    Question 78 marks
    Mark scheme ›
  8. 8
    Question 86 marks
    Mark scheme ›
  9. 9
    Question 96 marks
    Mark scheme ›
  10. 10
    Question 107 marks
    Mark scheme ›
  11. 11
    Question 115 marks
    Mark scheme ›
  12. 12
    Question 123 marks
    Mark scheme ›
  13. 13
    Question 137 marks
    Mark scheme ›

More 0478 papers

Other papers from Oct/Nov 2023

Solve it on ExamPalStart