Technology (given notes summarisation)

1. Engineering and Branches of Engineering

What is Engineering?

Engineering is the practical use of science, mathematics and technology to solve real-world problems and to design, create or improve:

• Products

• Structures

• Machines

• Systems

• Processes

Engineers cannot simply design anything they want. Their designs must work within requirements and constraints.

Common Engineering Constraints

Engineers need to consider:

• Safety — Is the design safe to use?

• Cost — Is it affordable?

• Materials — Are suitable materials available?

• Time — Can it be completed within the required time?

• Performance — Does it work effectively?

• Environmental impact — What effect does it have on the environment?

Key Definition

Engineering = using scientific, mathematical and technological knowledge to design solutions to practical problems.

Five Main Branches of Engineering

1. Mechanical Engineering

Mechanical engineering focuses on:

• Machines

• Moving parts

• Forces

• Motion

• Mechanical systems

Examples:

• Engines

• Bicycles

• Gear systems

• Pumps

• Manufacturing machines

Exam clue: If the question involves movement, machines, gears, forces or engines, think mechanical engineering.

2. Chemical Engineering

Chemical engineering combines:

• Chemistry

• Physics

• Engineering

It is used to produce, process or transform materials and chemicals.

Examples:

• Fuel processing

• Food production

• Water treatment

• Manufacturing materials

Exam clue: If substances are being processed, chemically changed or manufactured, think chemical engineering.

3. Computer Engineering

Computer engineering involves designing and developing:

• Computer hardware

• Computer systems

• Systems combining hardware and software

Examples:

• Processors

• Embedded controllers

• Computer systems

• Smart devices

Hardware

Hardware means the physical components of a computer or electronic system.

4. Biological Engineering

Biological engineering applies engineering principles to:

• Biology

• Living organisms

• Biological processes

• Living materials

Examples:

• Agricultural technologies

• Biological processes

• Engineered systems involving living materials

5. Civil Engineering

Civil engineering deals with:

• Infrastructure

• Structures

• The built environment

Examples:

• Roads

• Bridges

• Buildings

• Drainage systems

• Tunnels

Infrastructure

Infrastructure refers to the large systems and structures communities need to function, such as roads and bridges.

Important Vocabulary

Engineering: Using knowledge and design to solve practical problems.

Infrastructure: Large structures and systems needed by communities.

Hardware: Physical parts of a computer/electronic system.

System: A group of connected parts working together to perform a function.

2. The Engineering Design Process

The engineering design process is iterative, meaning engineers can move backwards and forwards between stages.

It is NOT always a straight line.

For example:

Design → Prototype → Test → Problem discovered → Modify → Test again

This cycle may happen several times before the final design is completed.

Stage 1 — Identify the Problem

Clearly determine:

• What problem needs to be solved?

• Who is the user?

• What does the solution need to achieve?

• What requirements must be met?

You need to understand the problem before designing solutions.

Stage 2 — Research and Investigate

Collect useful information about:

• Users

• Existing solutions

• Materials

• Mechanisms

• Safety

• Costs

• Constraints

• Possible technologies

Research helps engineers make informed decisions.

Stage 3 — Brainstorm Ideas

Generate multiple possible solutions.

Do not immediately choose the first idea.

Why brainstorm?

Because there may be many ways of solving the same problem.

Engineers can then:

Generate ideas → Compare ideas → Select the most suitable solution

Stage 4 — Select and Develop a Solution

Compare ideas against:

• Design criteria

• Requirements

• Constraints

Then develop the most suitable idea further using:

• Sketches

• Drawings

• Models

• Measurements

• Technical information

Stage 5 — Prototype

A prototype is a model or working version of a design.

Why make prototypes?

Prototypes allow engineers to:

• Test ideas

• Find weaknesses

• Examine performance

• Identify problems

• Make improvements

This happens before committing to the final product.

Stage 6 — Test

Testing measures how well the prototype performs.

Testing should be based on measurable design requirements, not personal opinions.

For example:

❌ "I like this bridge."

✅ "The bridge successfully supported the required 20 kg load."

The second answer provides evidence.

Stage 7 — Evaluate

Use the testing evidence to determine:

• What worked?

• What failed?

• Why did it happen?

• Did the design meet the criteria?

• What needs improvement?

Stage 8 — Modify and Improve

Change the design based on evidence.

Then test the improved design again.

If a prototype fails:

Do NOT simply give up.

Use:

Test → Evaluate → Identify problem → Modify → Retest

A failed test is useful because it provides information about what needs improvement.

Stage 9 — Communicate and Document

Engineers record:

• Ideas

• Sketches

• Drawings

• Decisions

• Materials

• Test results

• Problems

• Modifications

• Final conclusions

Why is documentation important?

It allows engineers to:

• Organise their work

• Track decisions

• Communicate ideas

• Explain changes

• Provide evidence

• Show how the final solution was developed

Design Process — Memorise This Order

Identify → Research → Brainstorm → Select/Develop → Prototype → Test → Evaluate → Modify → Communicate/Document

3. Forces: Contact and Non-Contact

What is a Force?

A force is a push or pull that can affect:

• An object's motion

• An object's direction

• An object's speed

• An object's shape

Force is measured in:

Newtons (N)

Forces have:

• Magnitude/size

• Direction

Arrows are commonly used in diagrams to represent forces.

Contact Forces

A contact force occurs when objects/materials physically interact or touch.

Applied Force

A push or pull applied by a person or another object.

Example: Pushing a shopping trolley.

Friction

A force that opposes relative motion between surfaces that are touching.

Example: A ball slows down while rolling across grass because of friction.

Normal Force

A supporting force exerted by a surface.

It acts perpendicular (90°) to the surface.

Example: A book sits on a desk.

• Gravity pulls downward.

• Desk provides normal force upward.

Tension

A pulling force transmitted through:

• Rope

• Cable

• String

• Similar materials

Example: A rope holding a hanging object.

Compression

A squeezing/pushing force that tends to shorten a material.

Think:

Compression = SQUASH

Shear

A force that causes adjacent sections of a material to try to slide past each other.

Think:

Shear = SLIDE

Spring Force

A restoring force produced when a spring is:

• Stretched

• Compressed

The spring tends to return towards its original shape.

Drag / Air Resistance

A resistive force acting against an object moving through a fluid.

A fluid can include:

• Air

• Water

Example: Air resistance acts against a falling parachutist.

Non-Contact Forces

Non-contact forces act without physical contact.

There are three major examples.

Gravitational Force

Attraction between masses.

Near Earth:

Gravity pulls objects towards Earth.

Magnetic Force

Attraction or repulsion caused by magnetic fields.

Magnets can:

• Attract

• Repel

Electrostatic Force

Attraction or repulsion between electrically charged objects.

Balanced vs Unbalanced Forces

Balanced Forces

Balanced forces have:

Net force = 0 N

They do not cause acceleration.

An object can:

• Remain stationary

• Continue moving at constant velocity

Example

A book resting on a desk:

↑ Normal force

📕 Book

↓ Gravity

If the forces are equal, they are balanced.

Unbalanced Forces

Unbalanced forces produce:

Net force ≠ 0 N

This causes acceleration.

Acceleration can mean:

• Speeding up

• Slowing down

• Changing direction

4. Newton's Laws of Motion

You MUST know all three laws.

Newton's First Law — Inertia

An object will:

• Remain at rest, OR

• Continue travelling at constant velocity in a straight line

unless a net external/unbalanced force acts upon it.

Inertia

Inertia is an object's tendency to resist changes in its motion.

Example: Car Braking

A car suddenly stops.

The passenger's body tends to continue moving forward because of inertia.

The seat belt provides the force needed to change the passenger's motion.

Soccer Ball Example

Why does a soccer ball remain stationary until kicked?

Because no unbalanced force is causing it to move.

The kick provides the force that changes its motion.

Smooth Floor vs Grass

A ball rolls further on a smooth floor because there is less friction.

Less friction means less force opposing the ball's motion.

Newton's Second Law

Newton's Second Law connects:

• Force

• Mass

• Acceleration

Formula

F = m × a

Where:

F = force in newtons (N)
m = mass in kilograms (kg)
a = acceleration in metres per second squared (m/s²)

Relationship

For the same mass:

More force → More acceleration

For the same force:

More mass → Less acceleration

Worked Example

A trolley has:

Mass = 5 kg
Acceleration = 2 m/s²

Formula:

F = m × a

Substitute:

F = 5 × 2

Therefore:

F = 10 N

Calculation Examples

6 kg × 3 m/s²

F = 6 × 3

F = 18 N

4 kg × 5 m/s²

F = 4 × 5

F = 20 N

8 kg × 2 m/s²

F = 8 × 2

F = 16 N

3 kg × 7 m/s²

F = 3 × 7

F = 21 N

9 kg × 4 m/s²

F = 9 × 4

F = 36 N

Exam Tip

For calculation questions, show:

Formula → Substitution → Calculation → Unit

For example:

F = m × a
F = 9 × 4
F = 36 N

Don't forget N.

Newton's Third Law — Action and Reaction

Newton's Third Law states:

When one object exerts a force on another object, the second object exerts an equal-sized force in the opposite direction on the first object.

A very important detail:

The two forces act on DIFFERENT objects.

Walking

Your foot pushes:

Ground ← backwards

The ground pushes:

You → forwards

This allows you to walk forward.

Swimming

Swimmer pushes:

Water ← backwards

Water pushes:

Swimmer → forwards

Jumping

Your feet push:

Ground ↓

The ground pushes:

You ↑

This pushes you upward.

Balloon

Balloon pushes:

Air →

Air pushes:

Balloon ←

Therefore, the balloon moves opposite to the escaping air.

The Three Laws — Quick Memory

First Law

INERTIA

Objects resist changes in motion.

Second Law

F = m × a

Force causes acceleration.

Third Law

ACTION ↔ REACTION

Equal-sized, opposite-direction forces acting on different objects.

5. Energy in Engineered Systems

Potential Energy

Potential energy is stored energy associated with an object's position or condition.

Two important examples are:

Gravitational Potential Energy

Energy stored because of an object's height/position in a gravitational field.

Generally:

Greater height → Greater gravitational potential energy

Example:

A ball sitting on a high shelf.

Elastic Potential Energy

Energy stored when an elastic object is:

• Stretched

• Compressed

Examples:

• Stretched elastic band

• Compressed spring

Kinetic Energy

Kinetic energy is the energy an object has because it is moving.

Examples:

• Moving bicycle

• Rolling ball

• Spinning fan

• Moving vehicle

Memory trick:

Kinetic = movement

Energy Transformations

Energy can be transformed from one form into another.

Falling Ball

At the top:

Gravitational potential energy

As it falls:

Potential energy → Kinetic energy

Electric Motor

Electrical energy → Kinetic/mechanical energy

Vehicle Engine

Fuel contains chemical energy.

The engine transforms this into mechanical effects that produce movement.

Some energy is also transferred to the surroundings as:

• Heat

• Sound

Simplified:

Chemical energy → Motion + Heat + Sound

6. Simple Machines

Simple machines make work easier by changing how a force is applied.

IMPORTANT:

Simple machines DO NOT create energy.

A machine may allow you to apply a smaller force, but usually the force then acts through a greater distance.

There are six simple machines to know.

1. Lever

A rigid bar that rotates/pivots around a fixed point.

Lever Vocabulary

Fulcrum = pivot point

Effort = input force

Load = object/resistance being moved

Examples:

• Seesaw

• Crowbar

• Bottle opener

2. Wedge

A wedge is essentially a moving inclined plane.

It concentrates force over a smaller area.

Used to:

• Cut

• Split

• Lift

• Separate

Examples:

• Knife

• Axe

• Chisel

3. Wheel and Axle

A large wheel connected to a smaller axle.

When one rotates, the other rotates.

It can help multiply:

• Force

• Speed

Examples:

• Doorknob

• Steering wheel

4. Pulley

A grooved wheel containing a:

• Rope

• Cable

• Cord

A pulley can change the direction of a force.

Multiple pulleys can reduce the effort force needed to lift a load.

Examples:

• Flagpole

• Lifting systems

5. Inclined Plane

A sloping surface.

It allows an object to be raised over a greater distance using less input force compared with lifting vertically.

Example:

• Ramp

6. Screw

A screw is:

An inclined plane wrapped around a cylinder.

It converts:

Turning/rotary motion → Linear movement

It can be used to:

• Fasten

• Lift

Examples:

• Bolt

• Screw jack

Simple Machines — Quick Revision

7. Types of Motion

There are four main types you need to identify.

Linear Motion

Movement along a straight path from one position to another.

Example:

Lift moving vertically

Memory:

Linear = line

Rotary Motion

Continuous circular movement around an axis.

Examples:

• Wheel

• Drill bit

Memory:

Rotary = rotation

Reciprocating Motion

Repeated backwards-and-forwards movement along a straight line.

Example:

Piston moving up and down

Memory:

Straight + back-and-forth = reciprocating

Oscillating Motion

Repeated backwards-and-forwards movement through an arc around a pivot.

Example:

Windscreen wiper

VERY IMPORTANT COMPARISON

Students often confuse reciprocating and oscillating motion.

Reciprocating

↕ / ↔

Straight back-and-forth

Example: piston

Oscillating

↶ ↷

Back-and-forth around a pivot/through an arc

Example: windscreen wiper

Motion Identification Shortcut

Straight one-way path → LINEAR

Continuous turning → ROTARY

Straight back-and-forth → RECIPROCATING

Arc/pivot back-and-forth → OSCILLATING

8. Basic Engine Performance

An internal-combustion engine needs suitable operating conditions to work effectively.

Two important factors are:

1. Fuel/air mixture

2. Engine speed

Fuel/Air Mixture

Fuel requires oxygen from the air for combustion.

Therefore, the proportion of:

Fuel : Air

affects how effectively combustion occurs.

An unsuitable mixture may cause:

• Reduced performance

• Increased fuel consumption

• Increased unwanted emissions

• Inefficient combustion

Engine Speed

Engine speed describes how quickly the engine rotates.

It is commonly measured in:

RPM = Revolutions Per Minute

Changes in engine speed affect:

• Operating conditions

• Rate at which the engine completes cycles

Exam Definition

RPM measures the number of revolutions completed in one minute.

9. Workshop and Safety Signs

Safety signs communicate:

• Hazards

• Required actions

• Prohibited actions

• Emergency information

• Fire equipment locations

You should identify safety signs using:

• Colour

• Shape

• Symbol

• Wording

Do not rely only on colour.

Mandatory Signs

Usually:

🔵 Blue + white symbol

Meaning:

YOU MUST DO SOMETHING

Example:

• Wear eye protection

• Wear hearing protection

• Wear safety equipment

Memory:

Mandatory = MUST

Warning Signs

Usually:

🟡 Yellow + black symbol/border

Meaning:

WARNING — HAZARD/DANGER

Used to alert people to potential hazards.

Prohibition Signs

Usually:

🔴 Red barred-circle symbol

Meaning:

YOU MUST NOT DO SOMETHING

Example:

• No smoking

• No entry

Memory:

Prohibition = prohibited/not allowed

Emergency / Safe-Condition Signs

Usually:

🟢 Green + white

Used for:

• Emergency exits

• First aid

• Safe conditions

• Emergency information

Memory:

Green = safe/emergency direction

Fire-Equipment Signs

Usually:

🔴 Red + white

Used to identify:

• Fire extinguishers

• Fire hoses

• Other firefighting equipment

Safety Sign Cheat Sheet

10. Vehicle Components and Diagram Labelling

For vehicle diagram questions, do not rely only on memorising words.

Use:

POSITION + FUNCTION

Ask yourself:

1. Where is the arrow pointing?

2. Where is that component normally located?

3. What does that component do?

Make sure the label line points to the actual component, not something nearby.

Bonnet / Hood

The panel covering the engine compartment at the front of many vehicles.

📍 Front/top of vehicle

Front Bumper

Protective exterior structure across the front of the vehicle.

📍 Very front/lower section

Its purpose includes helping protect the vehicle structure from minor impacts.

Headlight

Forward-facing light.

Used for:

• Illumination

• Visibility

📍 Front of vehicle

Windscreen

The large front window.

Functions:

• Allows the driver to see forward

• Protects occupants from airflow

• Protects occupants from debris

Side Mirror

Exterior mirror on the side of the vehicle.

Used to see areas:

• Beside the vehicle

• Behind the vehicle

Door

Body panel that opens to allow occupants to:

• Enter

• Leave

Can be hinged or sliding depending on the vehicle.

Wheel / Tyre

Wheel

Supports rotation around the axle.

Tyre

Provides the surface that contacts the road.

Don't automatically treat wheel and tyre as exactly the same component.

Front Fender / Guard

Body panel around the wheel opening.

It helps cover the wheel area.

Roof

Upper exterior body surface of the passenger compartment.

📍 Top of vehicle

Boot / Trunk

Rear storage compartment of a vehicle.

📍 Rear of vehicle

⭐ EXAM MASTER SHEET — WHAT YOU MUST MEMORISE

Engineering Branches

Mechanical → machines + movement
Chemical → chemicals + processing
Computer → hardware + computer systems
Biological → biology + engineering
Civil → infrastructure + structures

Engineering Design Process

Identify → Research → Brainstorm → Select/Develop → Prototype → Test → Evaluate → Modify → Document

Remember that the process is iterative, so engineers may return to earlier stages.

Forces

Contact:

Applied force, friction, normal, tension, compression, shear, spring, drag

Non-contact:

Gravity, magnetic, electrostatic

Balanced:

Net force = 0

Unbalanced:

Net force ≠ 0 → acceleration

🧠 NEWTON'S LAWS

1st = INERTIA

An object's motion stays unchanged unless a net external force acts.

2nd = FORMULA

F = m × a

Force = Newtons (N)
Mass = kilograms (kg)
Acceleration = metres per second squared (m/s²)

3rd = ACTION/REACTION

Equal-sized + opposite-direction forces acting on different objects

⚡ ENERGY

Potential

Stored energy

Examples:

• Raised object → gravitational potential

• Stretched/compressed spring → elastic potential

Kinetic

Movement energy

Transformation example

Potential → Kinetic

⚙ SIX SIMPLE MACHINES

Memorise all six:

Lever
Wedge
Wheel & axle
Pulley
Inclined plane
Screw

And remember:

Fulcrum = pivot

Effort = input force

Load = resistance/object moved

🔄 FOUR TYPES OF MOTION

Linear = straight movement

Rotary = continuous circular movement

Reciprocating = straight back-and-forth

Oscillating = back-and-forth around a pivot/arc

🚗 ENGINE PERFORMANCE

Fuel/air mixture affects combustion and performance.

Engine speed = how quickly the engine rotates.

RPM = Revolutions Per Minute

⚠ SAFETY SIGNS

BLUE → Mandatory → MUST DO

YELLOW → Warning → HAZARD

RED BAR → Prohibition → MUST NOT

GREEN → Emergency/Safe condition

RED/WHITE → Fire equipment

🚘 VEHICLE PARTS

Know the location and function of:

Bonnet / Hood
Front bumper
Headlight
Windscreen
Side mirror
Door
Wheel / tyre
Front fender / guard
Roof
Boot / trunk