← IGCSE Computer Science Paper 1

Microphone

An input device that turns sound waves into an analogue electrical signal, which an ADC converts to digital data so the computer can record or process voice.

Part of: IGCSE Computer Science 0478 — 3.2 Input and Output Devices — Module 5

Understanding Microphone in IGCSE Computer Science Paper 1

What it does: This is the first stage inside a microphone: the vibrating diaphragm is turned into a varying analogue electrical signal. The full chain shows the signal passing through the ADC, which converts it to digital data for the computer to record or process. A microphone sends sound data into the computer, so it is an input device. A speaker is the output device that sends sound out. Sound waves make the diaphragm vibrate. The ADC is a separate component that converts the signal later. Microphones capture voice for voice commands, calls and recording. Printing needs an output device, a printer.

Common mistakes: A microphone is an input device, so the sound must be taken in with INPUT, not sent out with OUTPUT. The line should be INPUT sound FROM microphone. A speaker is an output device that plays sound. To capture a voice command you need the input device, so the line should be sound ← MICROPHONE().

Class: _____________________  ·  Name: _____________________  ·  Date: _________

Free printable worksheet with full answer key — or add this module to a class and your students practise it interactively.

🖨 Print worksheet + answer key Add Microphone to a class →

This module's key terms are also in a printable crossword (Modules 240–251) and word search (Modules 240–261).

Take this worksheet further — free with Cloodit

Each concept is reinforced from every angle — learned, then applied, then tested.

Learning
Duo
A microphone is an input device or an output device?
Output deviceInput device
Matches
A microphone is an output device that plays sound out loud
↓
A microphone is an input device that captures sound. It is a speaker that plays sound out loud as output.
Applying
Meanings
Term
microphone
Meaning
An input device that turns sound waves into an analogue electrical signal, which an ADC converts to digital data so the computer can record or process voice.
Practice
sound ← MICROPHONE_INPUT()
Testing
Gaps
sound wave -> diaphragm -> signal
Check Answer
Spots
1OUTPUT sound FROM microphone
2signal ← ANALOGUE(sound)

Cloodit turns curriculum-aligned coding content into journeys students work through one biome at a time.

The 'Angelfish' badge — Reef Perfectionist, one of Cloodit's 106 collectible badges
Students earn collectable badges

Over 100 of them, across seven natural biomes.

Study Buddy
Students build a real study resource

Turns their work into revision material ready for Flash Cards and Exam study.

Diamond Dash — one of Cloodit's live, competitive Sprint games
Students lock in with Sprints

Live, competitive practice for the start of the lesson or a teacher-led lesson finisher.

A Cloodit certificate of achievement, ready to personalise and print
Custom printable certificates

Honour your top performers, or encourage a student who's trying hard — ready to print in seconds.

Add to class →

Quick Questions

1. A microphone is an input device or an output device?
A. Output device
B. Input device ✓
A microphone sends sound data into the computer, so it is an input device. A speaker is the output device that sends sound out.
2. What does a microphone convert sound waves into?
A. An electrical signal ✓
B. Light signals
Sound waves make a diaphragm move, and the microphone turns this movement into an electrical signal.
3. Which part of a microphone moves when sound waves hit it?
A. The diaphragm ✓
B. The ADC
Sound waves make the diaphragm vibrate. The ADC is a separate component that converts the signal later.
4. What type of signal does a microphone first produce?
A. Digital
B. Analogue ✓
The electrical signal from a microphone varies continuously, so it is analogue. It is digitised afterwards.
5. Which device converts the microphone's analogue signal into digital data?
A. Analogue-to-digital converter (ADC) ✓
B. Digital-to-analogue converter (DAC)
An ADC turns analogue into digital so the computer can process it. A DAC does the reverse, e.g. for speakers.

Match the Pairs

microphone → An input device that turns sound waves into an electrical signal the computer can use
ADC (analogue-to-digital converter) → Changes the microphone's analogue electrical signal into digital data the computer can process
Sound waves make the diaphragm move, and the microphone produces an analogue electrical signal → sound waves -> diaphragm moves -> analogue signal
A microphone's analogue signal must be digitised before the computer can record a voice → microphone -> analogue signal -> ADC -> digital data -> computer
A microphone is an output device that plays sound out loud → A microphone is an input device that captures sound. It is a speaker that plays sound out loud as output.
microphone -> digital data -> ADC -> computer → The microphone produces an analogue signal, not digital data. The ADC must convert the analogue signal to digital data afterwards.

Key Term

microphone
An input device that turns sound waves into an analogue electrical signal, which an ADC converts to digital data so the computer can record or process voice.

Fill in the Blanks

1. sound wave -> diaphragm -> analogue signal
Hint: Type the kind of electrical signal the microphone produces before conversion.
2. analogue signal -> ADC -> digital data
Hint: Type the kind of data the computer can process after conversion.
3. A microphone is an input device
Hint: Type the device category for something that sends data into a computer.
4. // The diaphragm vibrates when sound hits it
Hint: Type the name of the thin part inside the microphone that moves with sound waves.
5. voiceData ← ADC(micSignal)
Hint: Type the abbreviation of the converter that changes the analogue signal into digital data.

Spot the Error

Question 1
A OUTPUT sound FROM microphone
B signal ← ANALOGUE(sound)
C digital ← ADC(signal)
D STORE digital
Line A — A microphone is an input device, so the sound must be taken in with INPUT, not sent out with OUTPUT. The line should be INPUT sound FROM microphone.
Question 2
A IF voice_command = TRUE THEN
B sound ← SPEAKER()
C digital ← ADC(sound)
D ENDIF
Line B — A speaker is an output device that plays sound. To capture a voice command you need the input device, so the line should be sound ← MICROPHONE().
Question 3
A sound ← MICROPHONE()
B signal ← ANALOGUE(sound)
C digital ← ADC(signal)
D SEND signal TO computer
Line D — The analogue signal must first be converted by the ADC. The computer can only process the digital data, so the line should be SEND digital TO computer.
Question 4
A WHILE recording = TRUE
B signal ← MICROPHONE()
C digital ← ADC(signal)
D ENDIF
Line D — A WHILE loop must be closed with ENDWHILE, not ENDIF. The last line should be ENDWHILE.
Question 5
A command ← MICROPHONE()
B digital ← ADC(command)
C IF digital = 'lights on'
D TURN_ON light
Line C — The IF statement is missing the keyword THEN. The voice command check should read IF digital = 'lights on' THEN.

Student with a class code? Join your class →