Menu
Exam Questions

Edexcel GCSE Computer Science (1CP2) Exam Questions

Build a practice paper from 604 exam-style questions, each with its mark scheme and example answers. Print it, or answer it on paper and then open the mark schemes. Or browse the questions by topic.

Build a paper

Topics (none ticked: all of them)
Question types (none ticked: all of them)

Practice paper

4 questions · 11 marks

Pick again
Print
1Multiple choice1 markCharacter Sets Swap Remove

Characters are encoded using 7-bit ASCII.

Identify the number of different characters that can be represented using 7-bit ASCII.

[1 mark]
  • A64
  • B127
  • C128
  • D256
Mark scheme
  • C 128 (1)
  • The only correct answer is C. The correct answer is 128.
  • A is not correct because 6 bits give only 64 different combinations
  • B is not correct because 127 is the largest 7-bit value, not the number of characters that 7 bits can represent
  • D is not correct because 256 characters need 8 bits, as used by 8-bit extended ASCII
Example answers and how they were marked
Full marks1/1

C 128

Why: Selects the only correct option (1): 7 bits give 2 to the power of 7, which is 128 different characters.

No marks0/1

D 256

Why: Near miss scoring 0: 256 is the number of characters that 8 bits give in extended ASCII, not 7-bit ASCII.

No marks0/1

B 127

Why: Misconception scoring 0, the off-by-one error the examiners' report describes: 127 is the largest 7-bit value, but 7 bits give 128 different characters.

2Explain2 marksProtocols & Layers Swap Remove

Two computers exchange data over a network.

Explain why network protocols are needed for the two computers to communicate.

[2 marks]
Mark scheme

Award up to two marks for a linked explanation such as:

  • Devices (can) understand/interpret the data they receive (1) because they follow the same set of rules for communication (1)
  • Data is sent in an agreed format/structure (1) so the receiving device can interpret/understand it correctly (1)
  • Devices (can) connect/communicate successfully (1) because they agree how the data is transmitted, such as the type of signal used (1)
  • Errors (can) be detected/handled (1) because both devices follow the same rules for checking the data (1)

For both marks, the expansion must follow/associate with the statement.

Do not accept 'so devices can talk/communicate with each other' or 'so they can understand each other' without saying they follow the same rules/agreed format.

Do not accept an answer that only states protocols are a set of rules, without saying what this allows (e.g. the data can be understood/interpreted).

Do not accept a faster connection/speed as a reason why protocols are needed.

Do not accept naming a protocol (e.g. TCP/IP, HTTP, Wi-Fi) without an explanation of why it is needed.

Do not accept a description of what a protocol does (e.g. 'TCP splits data into packets') without saying why this is needed.

Example answers and how they were marked
Full marks2/2

Devices can understand the data they receive (1) because they follow the same set of rules for communication (1).

Why: Linked point (1) and reason (1): following the same rules is what lets the devices understand the data.

Some marks1/2

Data is sent in an agreed format (1).

Why: Point (1) identified, but no linked reason saying what the agreed format achieves.

No marks0/2

Protocols are needed so the connection is faster (0) because more data can be sent at once.

Why: Speed is not a reason protocols are needed, so there is no creditworthy point or linked reason.

3Calculate2 marksBinary Shifts Swap Remove

Computer systems manipulate bit patterns.

Complete the table with the result of applying the shift to the binary pattern.

[2 marks]
Binary patternShift8-bit binary result
0011 0100Logical shift left by 3
Mark scheme

Award one mark for each correct nibble in the correct order:

  • 1010 (1)
  • 0000 (1)

0 marks if the response is not 8-bit binary.

Example answers and how they were marked
Full marks2/2

1010 0000

Why: Every bit moves 3 places left, with 0s in from the right: both nibbles are correct (2).

Some marks1/2

1101 0000

Why: Shifts 2 places instead of 3. The second nibble is correct (1); the first is not.

No marks0/2

0000 0110

Why: Shifts the bits the wrong way. Neither nibble is correct.

4Discuss6 marksPurpose & Function of Operating Systems Swap Remove

A home computer is used to stream music, edit a video and download files at the same time.

Discuss how the operating system manages the processes running on the computer.

Your answer should include:

  • how the CPU is shared between processes
  • the states a process can be in
  • how the operating system responds when a process needs attention
[6 marks]
Mark scheme

Indicative content

How the CPU is shared between processes

  • The operating system uses multitasking to give each process a short time slice on the CPU, so the music, video editor and download appear to run at the same time.
  • The operating system decides which ready process will run next, so one program cannot keep the CPU to itself.
  • The operating system can stop a running process and move it back to ready when its time slice ends, so all processes make progress.

The states a process can be in

  • When a program is opened, the operating system creates a process and moves its instructions into RAM so it is ready.
  • The operating system moves a ready process to running when the CPU is free.
  • A running process becomes blocked when it is waiting for input or data, such as the download waiting for data to arrive.
  • When the process finishes, the operating system terminates it and releases the resources it was using.

How the operating system responds when a process needs attention

  • An interrupt is a signal to the CPU that needs immediate attention, so the operating system suspends the current process and runs the interrupt handler.
  • A hardware interrupt could be a printer out of paper, and a software interrupt could be an error in a program.
  • After the interrupt has been handled, the operating system can return the interrupted process to the CPU.

Levels

  • Level 0 (0 marks): No rewardable content.
  • Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
  • Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
  • Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Additional guidance

  • Level 3 responses must cover at least two of scheduling, process states and interrupts.
  • A response that only states that the OS 'manages processes' or gives a program a turn, without expansion, is limited to Level 1.
Example answers and how they were marked
Full marks6/6

The OS uses multitasking to share the CPU. It gives each process, such as the music player and the video editor, a small time slice so they appear to run at the same time. It decides which ready process is next and how long it runs. When the video editor is opened, the OS creates a process and moves its instructions into RAM so it is ready; when the CPU is free it moves it to running. If the download is waiting for data, the OS marks it blocked so the CPU is not wasted. If the printer runs out of paper, a hardware interrupt tells the CPU to stop and run the interrupt handler; afterwards the OS returns to the process.

Why: Covers scheduling with time slices, process states (ready, running, blocked) and interrupts, with sustained application to the music, video editor and download. Level 3.

Some marks4/6

The operating system uses multitasking so the music and video editor can run at the same time. It gives each program a small amount of time on the CPU. When a program is opened it creates a process and puts it in RAM. If a process is waiting for input it is blocked.

Why: Covers CPU sharing and process states, with some application, but says nothing about interrupts. Level 2.

Some marks1/6

The operating system manages processes by giving each program a turn on the CPU. This stops the computer crashing when too many programs are open.

Why: Gives only a basic, undeveloped point about giving each program a turn, with no linkage or application. Level 1.

Questions by topic

2.1 Binary

Build a paper on this topic 58
Adding Binary Numbers 6 questions Binary and Hexadecimal Basics 10 questions Binary Shifts 6 questions Binary to Denary Conversion 6 questions Binary to Hexadecimal Conversion 6 questions Denary to Binary Conversion 6 questions Denary to Hexadecimal Conversion 6 questions Denary to Negative Binary Conversion 6 questions Hexadecimal to Binary Conversion 6 questions

2.2 Data representation

Build a paper on this topic 56
Character Sets 18 questions Images 19 questions Sound 19 questions

2.3 Data storage and compression

Build a paper on this topic 24
Compression 18 questions Units & Conversion 6 questions

3.1 Hardware

Build a paper on this topic 77
Embedded Systems 17 questions Fetch Decode Execute Cycle 15 questions Primary Memory 15 questions Secondary Memory 15 questions Stored Program Computers 15 questions

3.2 Software

Build a paper on this topic 124
File Management 18 questions Memory Management 16 questions Peripheral Management 11 questions Process Management 12 questions Purpose & Function of Operating Systems 17 questions Software Basics 13 questions User Management 18 questions Utility Software 19 questions

3.3 Programming languages

Build a paper on this topic 37
Low and High Level Languages 19 questions Translators 18 questions

4.1 Networks

Build a paper on this topic 138
Addressing 16 questions LANs & WANs 16 questions Network Speed 5 questions Packet Switching 16 questions Protocols & Layers 17 questions The Internet 16 questions Topologies 17 questions Wired Connections 17 questions Wireless Connections 18 questions

4.2 Network security

Build a paper on this topic 36
Network Security Risks 18 questions Preventing Network Security Risks 18 questions

5.1 Environmental

Build a paper on this topic 36
E-waste 17 questions Manufacturing Technology 19 questions

5.2 Ethical and legal

Build a paper on this topic 18
Data Protection Act 14 questions Impact of AI 4 questions

More ways to revise Edexcel GCSE Computer Science (1CP2)

Activities Flashcards Revision notes

Teachers: build a paper, print it with the mark schemes at the end, and sign your school up to set your classes activities on every topic.

Fetch Decode Explain isn't affiliated with or endorsed by Pearson Edexcel.