Engineering Y9 ERC

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Mechanical Engineering

Focuses on the design, manufacturing, operation, and maintenance of machinery and mechanical components.

Computer Engineering

Integrates electronic engineering with computer science to design hardware and software systems.

Class 1 Lever

Places the fulcrum in the middle between the effort and the load (e.g., scissors, crowbar).

Class 2 Lever

Places the load in the middle between the fulcrum and effort (e.g., wheelbarrow, nutcracker).

Class 3 Lever

Places the effort in the middle between the fulcrum and load (e.g., tweezers, baseball bats).

Mechanical Advantage of Lever

Calculated as Effort Arm divided by Load Arm (MA = Effort Arm / Load Arm).

Mechanical Advantage of Inclined Plane

Calculated as Ramp Length divided by Vertical Height.

Single Fixed Pulley IMA

Has an Ideal Mechanical Advantage of 1.0 (changes direction only).

Toughness

Ability of a material to absorb energy and plastically deform without fracturing under impact.

Hardness

Measures a material's surface resistance to scratching, indentation, or abrasion.

Ductility

Property enabling materials (like copper) to be drawn into thin wires without breaking.

Malleability

Allows permanent plastic deformation under compressive force to form flat sheets (e.g., hammering/rolling).

Brittleness

Tendency of a material to fracture under load with little to no prior bending or stretching.

Torsional Force

Internal force attempting to twist a rotating shaft along its longitudinal axis.

Shear Force

Force acting parallel to a cross-section attempting to slide adjacent internal layers past one another.

Compressive Strength

Capacity to support heavy pushing or squeezing loads (e.g., concrete).

Composite Material

Combines materials to resist both tension and compression, such as reinforced concrete (rebar).

Environmental Engineering

Focuses on preventing, controlling, and eliminating pollution in air, water, and soil.

Wedge

Simple machine converting forward linear force into perpendicular splitting forces (e.g., an axe).

Bridge Deck

Primary horizontal roadway or pathway surface that directly carries traffic.

Bridge Abutments

Vertical support structures positioned at the extreme ends of a bridge to anchor it and retain soil.

Bridge Piers

Intermediate vertical columns placed in water or ground between bridge abutments.

Tension

Structural force defined as a pulling or stretching force acting outwards.

Compression

Structural force defined as a pushing or squeezing force acting inwards.

Dead Load

Stationary, permanent self-weight of the bridge structure itself.

Live Load

Weight of moving traffic, trains, cars, and pedestrians crossing a bridge.

Keystone

Wedge-shaped central stone at the top apex of a masonry arch that locks stones in place.

Gusset Plates

Thick steel plates used to join girders, beams, and truss members together at joints.

Triangulation in Truss

Rigid geometric shape (triangle) that resists distortion without altering side lengths.

Ironbridge

World's first cast-iron arch bridge, constructed in 1779 in Coalbrookdale, England.

Suspension Bridge

Bridge type that hangs its deck directly from vertical suspender cables connected to main overhead cables.

Sydney Harbour Bridge Type

Famous steel arch bridge opened in March 1932.

Sydney Harbour Bridge Pylons

Granite pylons serving decorative purposes only; no structural load-bearing role.

Resonance

Destructive phenomenon occurring when external forcing frequencies match a bridge's natural vibration frequency.

Coffer Dam

Temporary watertight enclosure pumped dry so piers can be built underwater.

Bridge Joining Techniques

High-strength bolting and electric welding largely replaced hot-driven riveting.

Workshop PPE

Safety glasses, protective apron, and fully enclosed leather shoes.

Newton's First Law (Inertia)

An object at rest stays at rest, and an object in motion stays in motion unless acted on by an unbalanced force.

Newton's Second Law

Acceleration of an object depends on its mass and the applied force (F = ma).

Newton's Third Law

For every action, there is an equal and opposite reaction.

Try Square

Tool used for marking out or testing 90-degree right angles and checking flatness.

Tenon Saw

Saw reinforced by a heavy back spine used for making straight, precise cuts in timber.

Bench Hook

Holds timber securely on the workbench while sawing and protects the benchtop.

Mallet

Wooden or rubber tool used instead of a steel hammer to avoid splitting wooden chisel handles.

Coping Saw

Hand saw designed with a thin, flexible blade to cut intricate curves and shapes in timber.

Electrical Engineering

The design, testing, manufacturing, construction, control, monitoring, and inspection of electrical/electronic devices, machinery, and systems.

Civil Engineering

The design, construction, maintenance, and inspection of large infrastructure projects like highways, bridges, and tunnels.

Aerospace Engineering

The design, manufacturing, and testing of aircraft, spacecraft, airframes, powerplants, control/guidance systems, and avionics.

Nuclear Engineering

The design, construction, operation, and testing of systems involving the production, control, and detection of nuclear radiation.

Structural Engineering

The design, construction, and inspection of load-bearing structures like large commercial buildings and bridges.

Biomedical Engineering

The practice of designing systems, equipment, and devices for use in medicine by healthcare practitioners.

Chemical Engineering

The design of processes and equipment for refining raw materials and processing chemicals to make valuable products.

Concrete

A composite material with high compressive strength, low tensile strength, and great durability used in construction.

Steel

A metal alloy with high tensile strength, ductility, malleability, toughness, and corrosion resistance.

Glass

An amorphous material with high transparency and good thermal/electrical insulation.

Cast Iron

A metal alloy with very high compressive strength, heat retention, and wear resistance.

Plastic

A synthetic polymer material; lightweight, durable, chemical-resistant, and easily molded using heat and pressure.

Rubber

An elastomer; highly elastic, durable, abrasion-resistant, and provides technical/electrical insulation.

Wood

A natural organic composite with a high strength-to-weight ratio and strong thermal/acoustic insulation.

Torsion Strength

The maximum twisting stress a material can withstand before permanently deforming or failing under rotational forces.

Shear Strength

The maximum stress a material can endure when forces act parallel to its cross-section, causing internal layers to slide.

Corrosion Resistance

The capacity of a material to withstand chemical attack or environmental degradation like oxidation and rusting.

Boyle's Law

In a confined space at constant temperature, gas volume is inversely proportional to pressure.

Aerodynamic Drag

Fluid friction caused by air pushing against the moving chassis, resisting forward motion.

Bernoulli's Principle

Faster-moving fluids exert lower pressure, utilized in aerofoil wing shapes to generate lift.

Wheel and Axle Simple Machine

A wheel locked to a central rod (axle) that increases turning power.

Pulley Simple Machine

A grooved wheel and rope system used to lift loads or change pull direction.

Inclined Plane Simple Machine

A slanted surface that reduces required force by spreading work over a longer incline distance.

Screw Simple Machine

An inclined plane wrapped around a cylinder that converts rotational motion into linear holding force.

Incremental Launching Method (ILM)

Bridge construction method where the deck is built in sections at an abutment and pushed outward across piers.

CO2 Dragster Mass Limits

Total vehicle mass must be a minimum of 45g and a maximum of 170g.

Coanda Effect in Flight

Airflow naturally clings to the curved upper surface of a wing and is deflected downward, generating lift.

Angle of Attack

The angle between the wing chord line and oncoming relative airflow.

Aspect Ratio of Wings

Calculated as wingspan squared divided by wing area.

Parasitic Drag

Friction between air and aircraft surfaces that increases exponentially with airspeed.

Induced Drag

Aerodynamic drag that is a by-product of lift generated at wingtips, highest at low speeds.

Elevator Flight Control Surface

Horizontal tail stabilizer surface that moves up or down to adjust nose pitch angle.

Aileron Flight Control Surface

Control surfaces on trailing outer wing edges that move in opposite directions to roll the aircraft.

Rudder Flight Control Surface

Vertical tail fin that swivels left and right to control horizontal heading (yaw).

Definition of Engineering

The application of science and mathematics to solve practical problems.

Four Main Engineering Material Categories

Metals, ceramics, polymers and composites.

Tensile Strength

The maximum pulling stress a material can withstand before breaking.

Six Simple Machines

Lever, wheel and axle, pulley, inclined plane, wedge and screw.

Effort Force Formula

P = Load Weight / Mechanical Advantage.

Class 1 Lever Example

Seesaw: the fulcrum is between effort and load.

Class 2 Lever Example

Wheelbarrow: the load is between fulcrum and effort.

Class 3 Lever Example

Fishing rod: the effort is between fulcrum and load.

Beam Bridge Forces

Top is in compression; bottom is in tension.

Arch Bridge Forces

Loads travel through the arch in compression towards the abutments.

Suspension Bridge Forces

Main cables and hangers are in tension; towers are in compression.

Cable-Stayed Bridge Forces

Diagonal cables are in tension; towers are in compression.

Truss Bridge Forces

Top chord compression; bottom chord tension; diagonals resist structural forces.

Cantilever Bridge Forces

Overhanging sections balance tension and compression.

Cast-in-Situ Construction

Concrete is poured into formwork directly at the construction site.

Precast Concrete

Concrete components are manufactured off-site and transported into position.

Balanced Cantilever Construction

Bridge segments extend symmetrically outwards from supporting piers.

Caisson Foundation

A watertight structure used to construct foundations underwater.

Shell CO2 Dragster

Encloses wheels in a body; aerodynamic but often heavier.

Rail CO2 Dragster

Uses narrow rails and exposed wheels; lightweight but creates more turbulence.

Show or Classic Dragster

A custom-designed dragster prioritising appearance or traditional styling.