Edexcel GCSE Computer Science Active Recall Guide (1CP2)
Edexcel · GCSE
Edexcel GCSE Computer Science Active Recall Guide
Every topic of specification 1CP2 written as exam-style questions with the answers printed after them. 680 questions across 6 topics and 41 subtopics, covering the written paper and the theory behind the on-screen one.
- Edexcel
- GCSE
- Specification 1CP2
- 680 questions
Guide overview All 6 topics Sample questions Papers and weighting Look inside Questions and answers
What the exam asks of you
Edexcel GCSE Computer Science is two papers. Paper 1, Principles of Computer Science, is written, 1 hour 30 minutes, 75 marks, 50 per cent, with one compulsory question per topic. Paper 2, Application of Computational Thinking, is on screen, 2 hours, 75 marks, 50 per cent, and asks students to design, write, test and refine Python programs in their own IDE.
Paper 1 is recall of defined terms, processes and conversions. Paper 2 is programming, and the guide covers the principles it rests on rather than replacing time at a keyboard.
| Paper | Covers |
|---|---|
|
Paper 1 Principles of Computer Science |
COMPUTATIONAL THINKING DATA COMPUTERS NETWORKS ISSUES AND IMPACT |
|
Paper 2 Application of Computational Thinking |
PROBLEM SOLVING WITH PROGRAMMING |
What is in the guide
All 6 topics
Every topic has its own page with its subtopics, what it covers and sample questions.
Sample questions
Taken from the guide. Answer each one closed book first, then open the answer.
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Decomposition, abstraction and subprograms
A program models a game of noughts and crosses. Which details of a real game would abstraction remove?
Show the answer
Abstraction would remove the pen, the paper and the players’ appearance. The model keeps only the 3 × 3 grid, the marks and whose turn it is. -
Binary, states and unsigned integers
What is the smallest number of bits needed to give a unique code to each of 50 students?
Show the answer
Six bits are needed, since 2⁶ = 64 codes is enough for 50 students. Five bits give only 32 codes, which is too few. -
Von Neumann architecture and the fetch-decode-execute cycle
What are registers?
Show the answer
Registers are very small, very fast storage locations inside the CPU. Registers hold the instruction, address or data being worked on at that moment. -
LANs, WANs and the structure of the internet
Give two examples of a WAN.
Show the answer
The internet is the largest WAN. A bank linking its branches across the country uses a WAN as well. -
Environmental impact of digital devices
How does manufacturing digital devices harm the environment?
Show the answer
Metals such as cobalt, lithium and gold must be mined, which damages land and uses large amounts of water and energy. Factories also release carbon dioxide and other pollution. -
Readable code, debugging and testing
Explain why if total = 100: fails in Python.
Show the answer
A single = assigns a value and cannot be used as a test, so Python reports a syntax error. A comparison needs the double equals sign ==.
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Look inside
Questions for a subtopic print together and the answers for that section print after them.
- Computational Thinking107
- Data128
- Computers95
- Networks92
- Issues and Impact88
- Problem Solving with Programming170
- Why do computers use binary to represent data and program instructions?
- Which kinds of data does a computer store as binary?
- What is a bit?
- How many different states can a binary pattern of n bits represent?
- How many different values can a 5-bit pattern represent?
- What is the smallest number of bits needed to give a unique code to each of 50 students?
- What is an unsigned integer?
- What range of values can an 8-bit unsigned integer hold?
- State the place values of the bits in an 8-bit unsigned binary number, from left to right.
- A computer's circuits are built from transistors that act as switches with two states, on and off. The binary digits 1 and 0 map directly onto those two states.
- A computer stores numbers, text, sound and images as binary. Program instructions are stored as binary patterns too.
- A bit is a single binary digit, either 0 or 1. A bit is the smallest unit of data a computer can store.
- A pattern of n bits can represent 2ⁿ different states. Each extra bit doubles the number of states.
- A 5-bit pattern can represent 32 different values. Five bits give 2⁵ = 32 combinations.
- Six bits are needed, since 2⁶ = 64 codes is enough for 50 students. Five bits give only 32 codes, which is too few.
- An unsigned integer is a whole number with no sign, so it can only be zero or positive. Every bit adds to the size of the number.
- An 8-bit unsigned integer holds values from 0 to 255. The largest value is 2⁸ − 1 = 255.
- The place values are 128, 64, 32, 16, 8, 4, 2 and 1.
questions
Scroll sideways to turn through the pages.
Questions students ask first
What is on the on-screen paper?
Paper 2 asks you to design, write, test and refine Python programs in your own IDE, using the Programming Language Subset that Pearson publishes. It is 75 marks and 50 per cent.
The theory behind it is in the guide as Problem Solving with Programming, 170 questions. The typing practice is yours to do at a keyboard.
Which topics are on Paper 1?
Computational thinking, data, computers, networks, and issues and impact. There is one compulsory question on each, and no calculator is allowed. The full breakdown is here.
Do I need to memorise binary conversions?
Yes. No calculator is allowed on Paper 1, so binary and hexadecimal conversions, binary addition and shifts have to be done by hand. They have their own subtopics.
Is 1CP2 the same as the old 1CP1?
No. Pearson replaced 1CP1 with 1CP2, which removed the non-exam assessment and made the programming an on-screen examination instead. The code on your timetable settles it; this guide is 1CP2.
Edexcel GCSE Computer Science Active Recall Guide
Every question paired with its answer, grouped by topic and subtopic, ready to work in three passes.