IGCSE Computer Science (0478)
    • Chapter 6: Automated & Emerging Technologies
    • Data Representation
      • Introduction
      • Why computers use binary (how binary represents data)
      • Number system
        • Introduction
        • Number Conversions
        • Addition of Binary Numbers
        • Logical binary shifts (positive 8-bit integers)
        • Two’s Complement (Signed: Positive and Negative Numbers)
        • Use of the Hexadecimal System
      • Text, Sound and Image
        • Text, Sound and Images
        • File Types
      • Data storage and File compression
        • Measurement of the Size of Computer Memories
        • Lossless and Lossy File Compression

    Chapter 6: Automated & Emerging Technologies

    Table of Contents#

    #Topic
    6.1Automated Systems
    6.2Robotics
    6.3Artificial Intelligence
    6.4Expert Systems
    6.5Machine Learning
    —Past Paper Questions and Model Answers
    —Flash Cards
    —Glossary
    —Exam Command Words
    —The SCAR Formula

    6.1 Automated Systems#

    What is it?
    An automated system is a machine that works on its own — no human
    needs to press any buttons or make any decisions.
    It uses sensors to collect information, a microprocessor to
    think about it, and actuators to take action.
    Think of it like this: When your phone screen gets brighter when
    you step outside, you didn't do anything. A tiny sensor spotted the
    bright light. The processor thought "it's bright out there." The screen
    got brighter. All in less than a second — completely automatic.

    How It Works — The Control Loop#

    The system keeps doing the same thing over and over. This never-ending
    cycle is called a feedback loop. Here is how it works step by step:
    StepPartSimple ExplanationReal Example
    1SensorNotices something in the real worldCamera on Tesla detects a car 15m ahead
    2ADCTranslates the signal into numbers the processor can readConverts the distance measurement into binary
    3MicroprocessorChecks if that number is within the safe rangeIs 15m close enough to brake?
    4DecisionFine = do nothing. Not fine = tell the actuatorYes, too close — brake now
    5ActuatorDoes something physical in the real worldBrakes squeeze — car slows down
    6FeedbackStarts again immediatelyNow how far away is the car?

    What Is the ADC and Why Do We Need It?#

    Here is the key thing to understand.
    Sensors record the real world. The real world is analogue — things
    change smoothly and gradually. Temperature doesn't jump from 20°C to
    21°C in one snap. It drifts slowly through every tiny value in between.
    But computers only understand digital — 0s and 1s. Nothing in between.
    The ADC (Analogue-to-Digital Converter) is the translator.
    It turns the smooth real-world signal into the digital steps a
    computer can actually read.
    KEY EXAM POINT
    If a sensor produces analogue data (and most do), you MUST
    mention the ADC in your exam answer. Without the ADC,
    the microprocessor cannot read the sensor data.
    It only understands binary. Always say the process is continuous.

    Common Sensors — What They Detect#

    SensorWhat It DetectsWhere You See It
    TemperatureHow hot or cold something isGoogle Nest thermostat, greenhouse heating
    Light (LDR)How bright the light isPhone screen auto-brightness
    PressureForce being appliedSupermarket automatic sliding doors
    Motion (PIR)Movement nearbyRing doorbell, security lights
    HumidityHow much moisture is in the airGreenhouse climate control
    MoistureHow wet the soil isAutomatic garden sprinklers
    Gas / ChemicalHarmful gas levelsCarbon monoxide detector at home
    Sound (Acoustic)Sound or vibrationsSecurity system detecting broken glass
    Proximity / UltrasonicDistance to nearby objectsSelf-parking car
    pHHow acidic a liquid isWater treatment plant
    AccelerometerSudden movement or impactCar airbag — fires when crash detected
    PulseHeart rateApple Watch health tracking

    Good Things and Bad Things About Automated Systems#

    Good Things (Advantages)Bad Things (Disadvantages)
    Faster and more accurate than humansCosts a lot of money to set up
    Spots problems and acts straight away (real-time)Can be hacked by criminals
    Cheaper to run long-term than paying workersPeople stop learning skills because machines do everything
    Works all day and all night — never tiresCannot handle unusual or unexpected situations
    Same quality output every single timeIf one part breaks, the whole system can stop
    Safe to use in dangerous places humans cannot goNeeds experts to fix when things go wrong

    Where Automated Systems Are Used#

    Industry
    Amazon's robots pack and sort millions of orders every day
    Robotic arms in Tesla's factory weld car parts with perfect precision
    Cameras on conveyor belts spot damaged products and remove them automatically
    Transport
    Tesla Autopilot: sensors watch the road every millisecond and control the car
    Airplane autopilot: keeps the plane at the right height and speed automatically
    Self-parking cars: sensors scan the space, then the car steers itself in
    Agriculture
    Soil sensors check if plants need water and open valves automatically
    Drones scan crops from above and spray only the parts that need treatment
    Autonomous tractors drive themselves across fields using GPS
    Weather
    Weather stations measure temperature and wind, sending data to forecasters
    Flood sensors trigger flood gates automatically when water levels get too high
    Gaming
    VR headsets track your head movement and update the screen instantly
    Motion controllers turn your real arm movements into in-game actions
    Lighting
    Street lights switch on at dusk when the LDR detects it getting dark
    Security lights flick on when the PIR sensor detects someone moving nearby
    Science
    Nuclear power plants shut themselves down automatically if radiation spikes
    Hospital drip machines adjust the dose based on the patient's pulse sensor

    6.2 Robotics#

    What is it?
    Robotics is the subject that covers how to design, build, and control robots —
    physical machines that can move and do things in the real world.
    Think of it like this: A Roomba vacuums your floor by itself. Amazon
    robots carry shelves across warehouse floors without anyone driving them.
    A robotic arm in a factory welds the same car part thousands of times a day
    without getting tired or making mistakes. These are all robots.

    Three Things Every Robot Must Have#

    PartWhat It MeansReal Example
    Mechanical StructureThe physical body — it can move and touch thingsBoston Dynamics Spot's four legs
    Electrical ComponentsThe brain and senses — sensors, processor, motorsCameras, computer chip, hydraulic legs
    ProgrammableIt follows stored instructions — and those can be changedAmazon robot programmed with a floor map
    IMPORTANT EXAM NOTE
    Robots do NOT automatically have AI.
    Most factory robots just repeat the same movement over and over.
    They follow pre-written instructions — they do NOT think or learn.
    AI is only there if someone has specifically added it.

    Two Types of Robot#

    TypeWhat It MeansDoes It Replace Humans?Example
    IndependentWorks completely on its own — no human neededYes, completelyAmazon warehouse robot, Roomba
    DependentA human controls it using a screen or joystickNo — the human is still in chargeda Vinci surgical robot

    Where Robots Are Used#


    Good Things and Bad Things About Robots#

    Good Things (Advantages)Bad Things (Disadvantages)
    Works 24/7 with no breaks or holidaysCannot handle surprises or unusual situations
    Can work in dangerous places humans cannotPuts people out of work — unemployment rises
    More accurate and consistent than any humanPeople lose skills because robots do the work
    Cheaper in the long run than paying wagesVery expensive to buy and set up
    No mistakes caused by being tired or distractedCan be hacked and taken control of

    6.3 Artificial Intelligence#

    What is it?
    AI is about making computers behave in a way that seems intelligent —
    like reasoning, making decisions, learning from experience, and spotting patterns.
    Think of it like this: TikTok's For You Page feels like it reads your mind
    after just one day. Gmail spots a scam email before you even open it.
    Spotify makes a playlist that sounds like your best friend built it for you.
    ChatGPT answers questions it was never directly taught.
    That is all AI — and you use it every single day.
    EXAM SCOPE NOTE
    For IGCSE, you only need to know AI through two things:
    Expert Systems and Machine Learning.
    That is it. Nothing else is required.

    Five Characteristics of AI#

    These are the things that make AI different from normal programs:
    CharacteristicSimple ExplanationReal Example
    Simulates human behaviourActs like a thinking humanChatGPT writing an essay on a topic it wasn't directly taught
    Uses data and rulesLearns from millions of examples and follows logical rulesGmail spam filter trained on millions of real spam emails
    Can reasonJoins facts together to reach a conclusionBank system: unusual time + foreign country = block the card
    Learns and adaptsGets better by itself over timeNetflix recommendations improve the more you watch
    Analyses patternsSpots repeated trends in huge amounts of dataTikTok noticing you always stop scrolling for cooking videos

    6.4 Expert Systems#

    What is it?
    An expert system is a computer program that works like a human expert in one
    specific subject. You ask it questions and it gives you professional advice —
    just like a doctor, lawyer, or engineer would.
    Think of it like this: When your bank blocks your card at 3am because someone
    tried to use it abroad, no human at the bank did that. A rule fired automatically:
    IF the time is unusual AND the location is foreign AND the amount is above normal
    THEN block the card.
    Done. No human. Instant.
    That is an expert system.

    The Four Parts of an Expert System#


    How the Inference Engine Works — Step by Step#


    The Four Parts — Easy to Remember#

    PartWhat It DoesSimple Analogy
    Knowledge BaseStores all the facts and informationA giant textbook with every fact ever written about the subject
    Rule BaseStores all the IF-THEN decision rulesA list of instructions like "if it quacks and swims, it's a duck"
    Inference EngineReads the facts, applies the rules, reaches a conclusionThe doctor reading your test results and making a diagnosis
    InterfaceWhere you ask questions and get your answersThe website form, app screen, or chatbot you type into
    EXAM TIP
    Learn exactly these four parts. Past papers have directly asked you
    to fill in the blanks with these exact four words.
    Knowledge Base. Rule Base. Inference Engine. Interface.

    Where Expert Systems Are Used#

    SubjectWhat It DoesReal Example
    MedicineDiagnoses illnesses from symptomsMYCIN — diagnosed bacterial infections in the 1970s
    BankingSpots and blocks fraudulent transactionsRevolut, Visa blocking dodgy card payments instantly
    LawPredicts court outcomes from past casesLegal AI tools used in UK and US
    AgricultureIdentifies crop diseases from photosPlant disease apps used by farmers across India and Africa
    Tech SupportDiagnoses your problem before a human speaks to youApple Support bot, broadband troubleshooting tool
    EducationMakes your practice questions easier or harder based on your scoresKhan Academy's personalised learning

    Good Things and Bad Things#

    Good Things (Advantages)Bad Things (Disadvantages)
    Works like a real expert — accurate and consistentCosts a huge amount to build and keep updated
    Available 24 hours a day, 7 days a weekOnly knows what it was taught — nothing outside that
    Answers questions faster than any human expertFeels cold and robotic — no care or empathy
    Never retires — expert knowledge is saved foreverCannot use common sense — only applies its rules
    Same quality answer every single timeHas to be regularly updated as new knowledge is discovered

    6.5 Machine Learning#

    What is it?
    Machine Learning is a type of AI where the computer teaches itself by
    looking at lots of examples. Nobody writes the rules for it.
    It figures the rules out on its own from the data.
    Think of it like this: Spotify's Discover Weekly playlist.
    Nobody at Spotify manually picked those 30 songs for you.
    Spotify's system watched 600 million users — what they played, skipped,
    rewound, and saved — spotted patterns, and built a playlist just for you.
    A new one, every Monday, automatically.
    That is machine learning.

    Normal Programming vs Machine Learning#


    Where Machine Learning Is Used#

    What It DoesWhere You See It
    Recommends what to watch or listen to nextNetflix, Spotify, YouTube, TikTok
    Spots and blocks spam emailsGmail — stops billions of spam emails every single day
    Recognises your face to unlock your phoneiPhone Face ID
    Detects fraud the moment a dodgy payment is madeRevolut, Visa, PayPal
    Understands spoken words and commandsSiri, Alexa, Google Assistant
    Finds cancer in medical scans before a doctor mightGoogle DeepMind working with the NHS
    Calculates the fastest route based on live trafficGoogle Maps, Waze

    AI vs Machine Learning — What Is the Difference?#

    Artificial IntelligenceMachine Learning
    What it isMaking computers act intelligentlyA specific type of AI that learns from data
    Who writes the rules?Human experts write the rulesThe system finds its own rules from examples
    Does it change over time?Not always — expert systems stay fixedYes — adapts automatically with new data
    ExampleBank fraud expert systemTikTok For You Page, Netflix recommendations
    RelationshipThe bigger subjectA smaller part that lives inside AI

    Past Paper Questions and Model Answers#


    Q1 — Greenhouse Temperature [8 marks]#

    Describe how sensors and a microprocessor keep a greenhouse between 25°C and 30°C.
    Model Answer
    1.
    A temperature sensor reads the temperature continuously
    2.
    The data is sent to the microprocessor
    3.
    Because the data is analogue, it goes through the ADC to be converted to digital
    4.
    The microprocessor compares the reading to its stored safe range: 25°C to 30°C
    5.
    Temperature below 25°C → signal sent to switch on the heater / close the vents
    6.
    Temperature above 30°C → signal sent to switch off the heater / open the vents
    7.
    Temperature within range → nothing happens
    8.
    This whole process repeats over and over — it is the feedback loop
    SCAR: Sensor. Compare. Actuator. Repeat.
    Always mention ADC. Always say process is continuous.
    Always state what happens when the value is fine (no action).

    Q2 — Underground Mine [4 marks]#

    Describe how an automated system monitors temperature and oxygen in a mine.
    Model Answer
    1.
    Sensors for temperature and oxygen keep taking readings
    2.
    The ADC converts the analogue data to digital so the processor can read it
    3.
    Temperature drops too low → processor tells the heater to turn on
    4.
    Oxygen drops too low → processor opens the oxygen valve
    5.
    If levels cannot be restored, an alarm is triggered
    6.
    The loop repeats continuously — always watching

    Q3 — Garden Sprinkler [6 marks]#

    Describe how a microprocessor controls an automatic garden sprinkler.
    Model Answer
    1.
    A soil moisture sensor detects how dry the soil is
    2.
    Data goes to the microprocessor — through the ADC first as it is analogue
    3.
    Microprocessor compares the reading to a stored safe moisture level
    4.
    Soil too dry → signal sent to the actuator (water valve)
    5.
    Valve opens — sprinkler turns on and waters the garden
    6.
    Soil moisture is fine → nothing happens
    7.
    The process repeats continuously in a feedback loop

    Q4 — Characteristics of AI [3 marks]#

    Describe the characteristics of AI. (Any 3 earn full marks)
    Model Answer
    1.
    Simulates human behaviour — the machine acts and decides like a human would
    2.
    Uses data and rules — trained on huge datasets with logical rules guiding decisions
    3.
    Can reason — joins facts together using logic to reach a conclusion
    4.
    Learns and adapts — changes its own processes over time without reprogramming
    5.
    Analyses patterns — spots trends in data that humans would never notice

    Q5 — AI in a Robot [4 marks]#

    Explain how a robot uses AI.
    Model Answer
    1.
    The robot uses AI to make decisions from sensor data — not just follow fixed steps
    2.
    It uses rules learned from training data to decide what action to take
    3.
    Over time it learns from what happens and gets better at its job
    4.
    AI means it can cope with new situations it was never directly taught about

    Q6 — Two Parts of an Automated System [2 marks]#

    State two main components of an automated system.
    Model Answer
    Sensor — collects data from the physical environment
    Microprocessor — processes the data and decides what to do
    (Also fine to write: Actuator / ADC)

    Q7 — Robots in a Car Factory [3 marks]#

    Give THREE advantages of using robots on a car assembly line.
    Model Answer
    1.
    Robots work 24/7 without any breaks — more cars built consistently
    2.
    Robots are more precise — fewer mistakes in welding and painting
    3.
    Robots can work in dangerous conditions — fumes and heat that would harm humans

    Q8 — Expert System Fill in the Blanks [3 marks]#

    (Real W23 Past Paper Question)
    A car repair garage uses an expert system.
    Use these words to complete the sentences:
    inference engine / interface / knowledge base / rule base
    Model Answer
    The mechanic uses the interface to type in the symptoms and get a recommendation
    The knowledge base stores all the facts about car faults and what causes them
    The inference engine looks at the facts, applies the rules, and works out the diagnosis

    Q9 — Machine Learning [2 marks]#

    (Real W23 Past Paper Question)
    The expert system has machine learning capabilities.
    What does this mean?
    Model Answer
    The system can automatically update and improve itself based on new cases it sees
    It does this without a human reprogramming it — it teaches itself from experience

    Q10 — AI vs Machine Learning [3 marks]#

    State the difference between AI and Machine Learning.
    Model Answer
    1.
    AI means making machines act intelligently; ML is a type of AI where
    the machine learns from data automatically
    2.
    In AI, human experts write the rules; in ML the machine
    figures out its own rules from examples
    3.
    AI systems may stay fixed after being built; ML systems
    keep adapting as new data arrives

    Q11 — Expert System Components [4 marks]#

    Name and describe TWO components of an expert system.
    Model Answer
    Knowledge Base — stores all the facts and information about the subject
    (e.g. every known symptom and disease)
    Inference Engine — the part that reads the facts, applies the IF-THEN
    rules, and figures out the answer or recommendation for the user

    Q12 — Self-Parking Car [4 marks]#

    A self-parking car uses ultrasonic sensors.
    Describe how it works.
    Model Answer
    1.
    Ultrasonic sensors send out sound pulses and measure how far away obstacles are
    2.
    Data goes to the microprocessor — through the ADC to convert it to digital
    3.
    Processor compares the distance to a stored safe minimum value
    4.
    Too close → signals the actuators (steering and brakes) to adjust position
    5.
    The loop repeats continuously until the car is safely parked

    Q13 — ATMs vs Human Bank Tellers [5 marks]#

    One advantage and one disadvantage of an ATM compared to a human cashier.
    Model Answer
    Advantage
    ATMs work 24 hours a day, 7 days a week — you can get cash at any time,
    not just during bank opening hours
    They handle simple transactions faster than a human cashier
    Disadvantage
    ATMs can break down or get hacked — leaving you with no way to get your money
    Using ATMs instead of people means bank tellers lose their jobs and customers
    forget how to do basic in-branch banking


    Q14 — Specimen Paper 1B Q10(a) — Characteristics of AI [3 marks]#

    An expert system is an example of artificial intelligence.
    Describe what is meant by artificial intelligence.
    Model Answer (any 3 from the list below)
    1.
    AI simulates intelligent human behaviour in machines
    2.
    AI systems have a collection of data and rules that guide their decisions
    3.
    AI has the ability to reason — it uses logic to reach conclusions from facts
    4.
    AI has the ability to learn and adapt — it updates itself based on experience
    5.
    AI can analyse patterns — it spots trends in large amounts of data
    Exam Tip: This question is worth 3 marks.
    Write 3 separate, clear points. One short sentence each is enough.
    Use the exact words from the characteristics list — simulates, reason,
    learn and adapt, analyse patterns.

    Q15 — Specimen Paper 1B Q10(b) — Expert System Components [3 marks]#

    One component of an expert system is the knowledge base.
    Identify the three other components present in an expert system.
    Model Answer
    Rule Base
    Inference Engine
    Interface
    Exam Tip: These exact four words appear in fill-in-the-blank questions.
    Knowledge Base. Rule Base. Inference Engine. Interface.
    Learn all four. Spell them correctly.

    Q16 — Specimen Paper 1B Q10(c) — Machine Learning [1 mark]#

    An expert system can make use of machine learning.
    State what is meant by machine learning.
    Model Answer
    Machine learning is when a program has the ability to
    automatically adapt its own processes and/or data
    based on experience — without being manually reprogrammed
    Exam Tip: This is only 1 mark. One clear sentence is enough.
    The key phrase the mark scheme wants is:
    "automatically adapt its own processes and/or data"

    Q17 — June 2024 Paper 12 Q10(a) — Garage Expert System [3 marks]#

    A garage uses an expert system to help diagnose problems with cars.
    The expert system is an example of artificial intelligence.
    Describe one characteristic of AI.
    Model Answer (any 1 of these earns full marks)
    AI has the ability to reason — it uses rules and logic to reach conclusions,
    for example concluding that a car has a flat battery from the symptoms given
    AI has the ability to learn and adapt — it updates its own decision-making
    based on new cases it has seen, without being reprogrammed
    AI can simulate human behaviour — it makes decisions the way a human
    expert mechanic would, based on knowledge and rules

    Q18 — June 2024 Paper 12 Q10(b) — How the Garage Expert System Works [6 marks]#

    The expert system is an example of artificial intelligence.
    Explain how the expert system operates.
    Model Answer
    1.
    The mechanic types their question or the car's symptoms into the interface
    2.
    The inference engine takes this input and searches the knowledge base
    for relevant facts about car faults and their causes
    3.
    The inference engine then applies the IF-THEN rules stored in the
    rule base to those facts
    4.
    For example: IF the engine makes no sound AND the lights are dim
    THEN the battery is likely flat
    5.
    The inference engine uses this process to reach a conclusion or recommendation
    6.
    The diagnosis is sent back to the mechanic through the interface
    Exam Tip: For a "how does it operate" question on expert systems,
    always name all four parts and say what each one does.
    Show the flow: Interface → Inference Engine → Knowledge Base + Rule Base → Interface.

    Q19 — Oct/Nov 2023 Paper — Describe How an Expert System Operates [6 marks]#

    AI system is an expert system. Explain how an expert system operates.
    Model Answer
    1.
    The user interacts with the expert system through the interface —
    they type in their question or situation
    2.
    The inference engine receives the input and examines the knowledge base
    to find facts that are relevant to the query
    3.
    It then applies the IF-THEN rules from the rule base to those facts
    4.
    The inference engine works through the rules until it reaches a conclusion
    5.
    For example: IF the patient has a fever AND a cough AND breathlessness
    THEN consider pneumonia
    6.
    The conclusion or recommendation is returned to the user through the interface

    Q20 — Machine Learning Improving a Robot [3 marks]#

    A farmer uses a robot to plant seeds in a field.
    The robot is adapted to have machine learning capabilities.
    Explain how this will improve the robot.
    Model Answer
    1.
    The robot can learn from its past planting sessions — for example
    adjusting depth or spacing based on which seeds grew best
    2.
    It can automatically adapt its processes without a farmer or programmer
    having to manually update its instructions
    3.
    Over time the robot becomes more accurate and more efficient — improving
    its own performance based on patterns it has identified in real data
    Exam Tip: The word is "explain" — so do not just say what ML is.
    Say HOW it makes the robot better. Use the word "because" or "so that"
    to force yourself to give a reason.

    Q21 — Why Does an Expert System Need a Knowledge Base? [2 marks]#

    An expert system is an example of artificial intelligence.
    Explain why an expert system needs a knowledge base.
    Model Answer
    1.
    The knowledge base stores all the facts and information about the subject
    that the expert system needs to make decisions
    (e.g. every known car fault, every known disease and symptom)
    2.
    Without the knowledge base, the inference engine would have no facts
    to work with
    — it cannot apply its rules to nothing, so it cannot
    reach any conclusion or give any advice

    Q22 — State the Difference Between an Expert System and Machine Learning [2 marks]#

    State one difference between an expert system and machine learning.
    Model Answer (any 1 of these)
    An expert system uses rules written by a human expert;
    machine learning writes its own rules by finding patterns in data
    An expert system's knowledge stays fixed unless a human updates it;
    machine learning automatically adapts as new data arrives
    An expert system cannot learn from new cases on its own;
    machine learning improves itself over time without reprogramming

    Q23 — Advantages and Disadvantages of Expert Systems [4 marks]#

    Give two advantages and two disadvantages of using an expert system.
    Model Answer
    Advantages (any 2)
    Available 24/7 — never off sick, never on holiday
    Gives consistent and unbiased results every single time
    Can store and apply more knowledge than any single human expert
    Responds faster than a human expert would
    Disadvantages (any 2)
    Very expensive to build and maintain
    Can only use knowledge already stored in it — cannot handle
    questions outside its domain
    Gives cold, robotic answers — no empathy or human judgement
    Needs regular updates or the knowledge becomes outdated

    Q24 — Supervised vs Unsupervised Machine Learning [2 marks]#

    State the difference between supervised and unsupervised machine learning.
    Model Answer
    Supervised machine learning trains on data that has already been
    labelled — for example emails pre-labelled as spam or not spam.
    The system learns from the correct answers.
    Unsupervised machine learning trains on data that has no labels —
    the system finds its own patterns and groups in the data
    without being told what to look for
    Note: This point comes from the full syllabus content at
    the bottom of the official notes. It appears in some
    higher-level papers. Learn it as a bonus point.


    Q25 — ATM Proximity Sensor [1 mark]#

    (Feb/Mar 2025 — 0478/12/F/M/25 Q4a-i)
    A sensor is used to detect when a person stands within 1 metre of the ATM.
    Identify an appropriate sensor for the ATM to detect a person.
    Model Answer
    PIR sensor (Passive Infrared sensor)
    (Also accept: proximity sensor / ultrasonic sensor)

    Q26 — Role of Microprocessor in ATM Detection [3 marks]#

    (Feb/Mar 2025 — 0478/12/F/M/25 Q4a-ii)
    Describe the role of the microprocessor when the ATM detects a person.
    Model Answer
    1.
    The microprocessor receives the signal from the sensor
    (converting it from analogue to digital via the ADC if needed)
    2.
    It compares the sensor data to a stored threshold value
    — is a person within 1 metre?
    3.
    If the value confirms someone is nearby, the microprocessor
    sends a signal to the output device (the screen) to display
    the welcome message
    Exam Tip: Always structure a microprocessor answer as:
    receive data → compare to stored value → send signal to output.
    That earns all 3 marks.

    Q27 — Identify Three Other Characteristics of AI [3 marks]#

    (Feb/Mar 2025 — 0478/12/F/M/25 Q6a)
    One characteristic of AI is the ability to learn.
    Identify three other characteristics of AI.
    Model Answer (any 3 from the remaining 4)
    1.
    Simulates intelligent human behaviour
    2.
    Collection of data and rules
    3.
    Ability to reason
    4.
    Analyses patterns
    Exam Tip: This question gives you one for free and asks for three more.
    Do not write "ability to learn" again — you will get zero for a repeated point.
    Write three short, clean, distinct points. One line each.

    Q28 — Machine Learning in a Search Engine [3 marks]#

    (Feb/Mar 2025 — 0478/12/F/M/25 Q6b)
    A search engine uses machine learning.
    Explain how machine learning is used by the search engine.
    Model Answer
    1.
    The search engine collects data from millions of searches —
    what users searched for, which results they clicked on, and
    how long they stayed on each page
    2.
    It uses this data to identify patterns — for example,
    which results are most useful for a given search term
    3.
    The search engine automatically adapts its own ranking
    process over time, improving the results it shows without
    anyone reprogramming it
    Exam Tip: The word "explain" means you need to say HOW it works
    — not just define machine learning.
    Hit three things: collects data, finds patterns, adapts automatically.

    Q29 — Robotics: Characteristics of a Robot [3 marks]#

    (0478/11/M/J/23)
    A robot is used in a factory to pack boxes.
    State three characteristics of a robot.
    Model Answer
    1.
    A robot has a mechanical structure — a physical body that can
    move and interact with the world
    2.
    A robot has electrical components — sensors, a microprocessor,
    and actuators working together
    3.
    A robot is programmable — it follows a stored set of instructions
    that can be changed

    Q30 — Robotics: Independent vs Dependent [3 marks]#

    (0478/11/M/J/23)
    The factory also uses a robot arm that is controlled remotely
    by a human operator.
    State the type of robot this is and explain the difference
    between this type and a fully autonomous robot.
    Model Answer
    This is a dependent robot — it requires a human to control it
    through an interface and cannot operate on its own
    A fully autonomous (independent) robot operates without any
    human intervention — it makes all its own decisions
    The key difference is that a dependent robot supplements the human
    whereas an independent robot completely replaces the human role

    Q31 — Robotics: Hospital Robot [4 marks]#

    (0478/11/M/J/24)
    A hospital uses a robot to deliver medicines to patients in different
    wards. Describe two advantages and one disadvantage of using
    this robot instead of a human worker.
    Model Answer
    Advantages (any 2)
    1.
    The robot works 24/7 without rest — medicines can be delivered
    at any time of day or night without delays
    2.
    The robot is more consistent and precise — it delivers exactly
    the right dose to the right patient without human error
    Disadvantage (any 1)
    1.
    The robot is expensive to install and maintain — the hospital
    must invest heavily upfront and pay for technical specialists
    2.
    The robot cannot handle unexpected situations — if a patient
    is in a different location than expected, it may fail to adapt

    Q32 — Automated Systems: Flood Warning [4 marks]#

    (0478/11/M/J/24)
    A river uses an automated system to detect dangerous flood levels
    and trigger a warning siren.
    Describe how this automated system works.
    Model Answer
    1.
    A water-level sensor continuously measures the height of the
    river water
    2.
    The data is analogue — it passes through the ADC to be
    converted into digital binary before reaching the microprocessor
    3.
    The microprocessor compares the water level reading to a
    stored safe maximum value
    4.
    If the water level exceeds the threshold — the microprocessor
    sends a signal to the actuator (siren) to sound the alarm
    5.
    If the level is within the safe range — no action is taken
    6.
    The process repeats continuously — this is the feedback loop

    Q33 — Automated Systems: Two Benefits of Using Sensors [2 marks]#

    (0478/12/O/N/23)
    Give two benefits of using sensors in an automated system
    rather than relying on human observation.
    Model Answer
    1.
    Sensors can detect changes much faster than a human can
    notice and react — improving response time and safety
    2.
    Sensors work continuously without rest — they never get
    distracted, tired, or need a break, unlike a human observer

    Q34 — Automated Systems: Role of the ADC [2 marks]#

    (0478/12/O/N/24 — Q on sensor data)
    A temperature sensor in an automated greenhouse produces
    an analogue output.
    Explain why an ADC is needed before the microprocessor can
    use this data.
    Model Answer
    1.
    The temperature sensor produces an analogue signal —
    a continuously changing value with infinite possible levels
    2.
    The microprocessor can only process digital (binary) data —
    0s and 1s. The ADC converts the analogue signal into binary
    so the microprocessor can read and compare it

    Q35 — Robotics: Why Robots Cannot Replace Doctors [3 marks]#

    (0478/13/O/N/24)
    A hospital uses a robot to help diagnose patients.
    Explain why the robot cannot fully replace a human doctor.
    Model Answer
    1.
    The robot can only follow its pre-programmed instructions —
    it cannot handle new or unusual symptoms it was not programmed for
    2.
    A robot has no empathy or human judgement — it cannot pick up
    on how a patient is feeling emotionally or read non-verbal cues
    3.
    Without AI added to it, the robot cannot learn or adapt from
    new cases — a doctor improves with every patient they treat

    Q36 — AI vs Expert System vs Machine Learning [4 marks]#

    (0478/13/M/J/23 — Stretch Question)
    A hospital uses an expert system and a machine learning program
    to assist doctors.
    (a) Explain one way the expert system and machine learning
    program are similar.
    (b) Explain one way they are different.
    Model Answer
    (a) Similarity
    Both are examples of artificial intelligence — they both
    simulate intelligent human behaviour and make decisions
    based on stored knowledge and data
    (b) Difference
    An expert system uses rules written by human experts
    — it cannot update those rules on its own
    A machine learning program automatically adapts its own rules
    by finding patterns in new data — no human has to reprogram it

    Quick Revision Flash Cards#

    WordWhat It Means
    Automated SystemA machine that works on its own — no human has to press buttons or decide
    SensorA device that detects something in the real world — temperature, movement, light
    ADCTranslates the real-world signal into 0s and 1s the processor can read
    MicroprocessorThe brain — compares data to stored values and decides what to do
    ActuatorThe muscle — does something physical like turning on a motor or opening a valve
    Feedback LoopThe system keeps repeating: sense, compare, act, sense, compare, act...
    RobotA machine with a physical body, electrical parts, and stored instructions
    AIComputer software that acts in an intelligent, human-like way
    Expert SystemAI that acts like a professional expert in one specific subject
    Knowledge BaseWhere all the facts are stored in an expert system
    Rule BaseWhere all the IF-THEN rules are stored in an expert system
    Inference EngineThe part that reads the facts, applies the rules, and gives an answer
    InterfaceWhere the user types questions and reads answers in an expert system
    Machine LearningA type of AI that teaches itself by looking at examples — no human writes the rules

    Glossary#

    WordSimple Meaning
    AnalogueSomething that changes smoothly — like temperature drifting gradually upward
    DigitalOnly 0s and 1s — the only language computers understand
    Feedback LoopThe system keeps checking and acting, over and over, non-stop
    DeskillingWhen people forget how to do something because a machine does it for them
    HazardousDangerous — like radioactive areas, toxic fumes, or extreme heat
    Cyber-attackWhen a criminal tries to break into or damage a computer system remotely
    InferenceReaching a conclusion by thinking through the facts and rules logically
    SubsetA smaller category inside a bigger one — ML is a subset of AI

    Exam Command Words#

    WordWhat the Examiner Wants
    State / GiveJust write the fact — no explanation needed, keep it short
    DescribeWalk through it step by step — what happens, then what, then what
    ExplainSay WHY something happens, not just WHAT happens
    DiscussGive the good points AND the bad points
    IdentifyPoint something out from a diagram or description given to you
    CompareGive both similarities AND differences
    OutlineA short summary — just the most important points

    The SCAR Formula#

    Every time an exam question says "describe how an automated system works",
    use this four-letter formula. It covers everything the examiner wants.
    Every automated system answer needs four things:
    1.
    The specific sensor — name it and say what it detects
    2.
    The ADC — if the data is analogue
    3.
    What happens when the value is safe (nothing — no action)
    4.
    That the process is continuous / it is a feedback loop

    End of Chapter 6 — You have got this.
    Modified at 2026-03-24 10:30:05
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