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QCAA Engineering EA practice questions

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Question 1Engineering fundamentals and the engineering process

Which stage of the engineering design process immediately follows problem definition and identification of constraints?

  1. Manufacturing the final product
  2. Preparing maintenance manuals
  3. Testing the finished prototype
  4. Generating and evaluating possible solutions Correct answer.

Explanation

Once the problem and its constraints are clearly defined, engineers generate candidate solutions and evaluate them against criteria such as cost, safety and performance. Manufacturing, testing and documentation all occur later in the cycle.

Question 2Engineering fundamentals and the engineering process

A team builds a small bridge from balsa and loads it until it breaks. Recording the maximum load is best described as which activity?

  1. Destructive testing of a prototype Correct answer.
  2. Life-cycle assessment
  3. Reverse engineering
  4. Quality control of production

Explanation

Loading a prototype until failure is destructive testing, which reveals the strength limit of the design. It is a standard way to validate performance against design requirements.

Question 3Engineering fundamentals and the engineering process

Which statement best describes a constraint in an engineering brief?

  1. A desirable feature that improves a design
  2. A measurement taken during testing
  3. A sketch made early in the process
  4. A limit that any acceptable solution must satisfy Correct answer.

Explanation

Constraints are mandatory boundaries such as budget, deadline, materials or regulations that every viable solution must meet. Criteria, by contrast, are desirable qualities used to compare options.

Question 4Engineering fundamentals and the engineering process

In a formal engineering drawing, what does a third-angle projection symbol indicate?

  1. The tolerance applied to all dimensions
  2. How the views are arranged relative to the object Correct answer.
  3. The scale at which the drawing is printed
  4. The material from which the part is made

Explanation

The projection symbol tells the reader whether first-angle or third-angle arrangement is used, so the views are interpreted correctly. Material and tolerance information appear elsewhere, for example in the title block and notes.

Question 5Engineering fundamentals and the engineering process

Which unit is the SI base unit of force?

  1. watt
  2. joule
  3. pascal
  4. newton Correct answer.

Explanation

The newton is the SI unit of force, defined as the force that gives a one-kilogram mass an acceleration of one metre per second squared. Joule, pascal and watt measure energy, pressure and power respectively.

Question 6Engineering fundamentals and the engineering process

A steel beam is supported at both ends and carries a load at midspan. Which internal action is primarily induced at the centre of the span?

  1. Axial tension
  2. Torsion
  3. Bending moment Correct answer.
  4. Shear only

Explanation

A simply supported beam under a transverse load develops bending moments, largest near midspan, which produce compressive and tensile stresses across the section. Torsion would require a twisting load, and axial tension requires an end load along the axis.

Question 7Engineering fundamentals and the engineering process

What is the main purpose of a risk assessment before an engineering practical activity?

  1. To guarantee that no accident can ever occur
  2. To decide which student leads the team
  3. To record the final results of the experiment
  4. To identify hazards and reduce the likelihood or severity of harm Correct answer.

Explanation

Risk assessment systematically identifies hazards and puts controls in place to lower the chance or consequence of injury. It cannot eliminate all risk, and it is completed before work begins rather than after.

Question 8Engineering fundamentals and the engineering process

Which of the following is an example of a renewable energy source used in engineering systems?

  1. Diesel
  2. Wind Correct answer.
  3. Natural gas
  4. Black coal

Explanation

Wind is naturally replenished and produces no direct combustion emissions, making it renewable. Natural gas, diesel and black coal are finite fossil fuels that release stored carbon when burned.

Question 9Engineering fundamentals and the engineering process

An engineer needs a material that is electrically insulating, lightweight and easily moulded into complex shapes for a low-cost housing. Which class of material best suits these requirements?

  1. Aluminium alloy
  2. Thermoplastic polymer Correct answer.
  3. Mild steel
  4. Soda-lime glass

Explanation

Thermoplastics are lightweight electrical insulators that can be moulded cheaply into complex shapes, matching all three requirements. The metals conduct electricity, and glass is relatively dense and less suited to complex moulding at low cost.

Question 10Engineering fundamentals and the engineering process

A pulley system has a mechanical advantage of 4 and is used to lift a 200 N load. Ignoring friction, what effort force is required?

  1. 50 N Correct answer.
  2. 200 N
  3. 800 N
  4. 400 N

Explanation

Mechanical advantage equals load divided by effort, so effort equals load divided by mechanical advantage, giving 200 divided by 4, which is 50 N. Friction would increase the required effort above this ideal value.

Question 11Engineering fundamentals and the engineering process

A simply supported beam of span 4 m carries a point load of 12 kN at its midpoint. What is the magnitude of each support reaction, ignoring the beam's self-weight?

  1. 12 kN
  2. 24 kN
  3. 6 kN Correct answer.
  4. 3 kN

Explanation

Because the load is central and the beam is symmetrically supported, each reaction carries half the load, so 12 divided by 2 equals 6 kN. Vertical equilibrium confirms the two reactions sum to the applied load.

Question 12Engineering fundamentals and the engineering process

A component must be made in large numbers with consistent dimensions and a smooth finish. Which manufacturing process is most appropriate?

  1. Injection moulding Correct answer.
  2. Hand lay-up of composite
  3. Sand casting of individual parts
  4. Manual arc welding

Explanation

Injection moulding uses a reusable mould to produce high volumes of identical parts with good surface finish and low unit cost. Hand processes and welding are slower and less repeatable, and sand casting typically gives a rougher finish.

Question 13Engineering fundamentals and the engineering process

In an orthogonal drawing, a dimension is given as 25.0 with a tolerance of plus or minus 0.2 mm. Which measured size would be accepted?

  1. 25.25 mm
  2. 25.15 mm Correct answer.
  3. 24.70 mm
  4. 24.75 mm

Explanation

The acceptable range is 24.8 mm to 25.2 mm. Only 25.15 mm falls inside this band; the other values lie outside the permitted limits.

Question 14Engineering fundamentals and the engineering process

A designer selects a material with high strength-to-weight ratio for an aircraft wing component. Which property combination is being prioritised?

  1. High thermal conductivity with low strength
  2. High yield strength with low density Correct answer.
  3. High electrical resistance with low melting point
  4. High density with high stiffness

Explanation

Strength-to-weight ratio compares load-carrying capacity with density, so a high value requires strong, light material. Low density reduces the mass that the aircraft structure must support.

Question 15Engineering fundamentals and the engineering process

A team compares three concept designs using a weighted decision matrix. What is the main advantage of this method?

  1. It makes the comparison of options against criteria transparent and traceable Correct answer.
  2. It removes the need for any prototype testing
  3. It calculates the exact manufacturing cost
  4. It guarantees the chosen design will succeed

Explanation

A weighted decision matrix scores each concept against agreed criteria and weights, making trade-offs visible and defensible. It supports judgement but cannot guarantee success or replace physical testing and costing.

Question 16Engineering fundamentals and the engineering process

A motor lifts a 50 kg load through 4 m in 10 s. Taking gravitational acceleration as 10 m/s squared, what is the average output power?

  1. 200 W Correct answer.
  2. 2000 W
  3. 20 W
  4. 500 W

Explanation

Work equals force times distance, giving 500 N times 4 m, which is 2000 J. Power is work divided by time, so 2000 J divided by 10 s equals 200 W.

Question 17Engineering fundamentals and the engineering process

Which change would most improve the fatigue life of a steel shaft subjected to repeated reversed bending?

  1. Adding a sharp keyway near the midspan
  2. Increasing the shaft diameter only at the bearing ends
  3. Increasing the surface roughness to aid grip
  4. Removing sharp changes in section and polishing the surface Correct answer.

Explanation

Fatigue cracks usually initiate at stress concentrations and surface defects, so smooth transitions and a polished finish raise fatigue life. Sharp features such as keyways concentrate stress and accelerate crack initiation.

Question 18Engineering fundamentals and the engineering process

A quality team plots measured shaft diameters on a control chart. What does a point outside the control limits most likely indicate?

  1. A special cause of variation requiring investigation Correct answer.
  2. Normal random variation within the process
  3. That the specification limits have changed
  4. That the measurement instrument is faulty

Explanation

Control limits describe the natural variation of a stable process, so a point beyond them signals an unusual, assignable cause. Such signals prompt investigation rather than automatic acceptance.

Question 19Engineering fundamentals and the engineering process

An engineer must choose between two pumps with the same duty. Pump A costs less but needs frequent maintenance; Pump B costs more but has low maintenance. Which approach best supports a defensible choice?

  1. Choose Pump A purely because its purchase price is lower
  2. Choose Pump B purely because it looks more modern
  3. Defer the decision until both pumps fail in service
  4. Compare total life-cycle cost including purchase, energy and maintenance Correct answer.

Explanation

Life-cycle costing sums purchase, operating, maintenance and disposal costs over the service life, giving a fair comparison. Selecting on purchase price alone ignores the higher running costs of Pump A.

Question 20Engineering fundamentals and the engineering process

A cantilever beam of length 2 m carries a point load of 5 kN at its free end. What is the magnitude of the bending moment at the fixed support?

  1. 10 kN·m Correct answer.
  2. 2.5 kN·m
  3. 5 kN·m
  4. 20 kN·m

Explanation

For a cantilever with an end point load, the maximum moment at the support equals load times length, so 5 kN times 2 m equals 10 kN·m. The moment decreases linearly to zero at the free end.

Question 21Engineering fundamentals and the engineering process

Which pair correctly matches an engineering standard's role with an example of its benefit?

  1. Standards remove the need for testing by manufacturers
  2. Standards guarantee that products will never fail
  3. Standards are optional documents with no legal effect anywhere
  4. Standards specify consistent requirements, enabling interchangeability of parts Correct answer.

Explanation

Standards set agreed requirements and methods so that parts and processes are consistent and interchangeable across suppliers. They support quality but cannot guarantee freedom from failure or replace testing.

Question 22Engineering fundamentals and the engineering process

A truss member is found to carry a compressive force. Which design change most directly reduces the risk of buckling in that member?

  1. Reducing its unbraced length Correct answer.
  2. Changing its material to one with lower stiffness
  3. Increasing its slenderness ratio
  4. Reducing its cross-sectional area

Explanation

Buckling capacity falls as the unbraced length rises, so shortening the effective length by bracing raises the critical load. Increasing slenderness or reducing area lowers resistance, and lower stiffness also reduces buckling capacity.

Question 23Engineering fundamentals and the engineering process

A closed-loop control system maintains oven temperature. Which change best explains how negative feedback improves steady performance?

  1. The controller acts on the error between setpoint and measured output Correct answer.
  2. The controller removes the sensor from the loop
  3. The controller increases gain until the error becomes infinite
  4. The controller ignores the measured output and runs open loop

Explanation

Negative feedback compares the measured output with the setpoint and drives the actuator to reduce the error. This correction lets the system reject disturbances and hold the setpoint more closely than open-loop control.

Question 24Engineering fundamentals and the engineering process

Two otherwise identical beams are made from materials with the same density, but one has twice the Young's modulus. For the same load and geometry, how does the stiffer beam behave in the elastic range?

  1. It deflects about twice as much
  2. It deflects about half as much Correct answer.
  3. It develops no bending stress
  4. It carries twice the load before yielding

Explanation

Elastic deflection is inversely proportional to Young's modulus for a given load and geometry, so doubling the modulus roughly halves the deflection. Yield strength, not stiffness, governs the load at which yielding begins.

Question 25Engineering fundamentals and the engineering process

A product is assessed over its full life cycle. Which comparison best reflects a life-cycle approach rather than a manufacturing-only view?

  1. Including raw material extraction, use-phase energy and end-of-life disposal Correct answer.
  2. Considering only the retail price to customers
  3. Counting only the factory assembly hours
  4. Measuring only the mass of the finished product

Explanation

Life-cycle assessment spans extraction, production, use and disposal, capturing impacts that occur outside the factory. Narrow measures such as assembly hours or retail price miss most of the environmental burden.

Question 26Engineering fundamentals and the engineering process

Which stage of the engineering design process immediately follows the identification of a need or problem?

  1. Selecting the final manufacturing process
  2. Defining the problem and constraints Correct answer.
  3. Building a physical prototype
  4. Marketing the finished product

Explanation

After a need is identified, engineers must define the problem clearly, including constraints and criteria, before generating solutions. This definition guides all later design work and ensures the solution addresses the real need.

Question 27Engineering fundamentals and the engineering process

In a team-based engineering project, what is the primary purpose of maintaining a design journal?

  1. To replace the need for formal technical drawings
  2. To satisfy legal requirements for patent applications
  3. To record decisions, calculations and changes for traceability Correct answer.
  4. To advertise the team's progress to competitors

Explanation

A design journal provides a chronological record of ideas, decisions, calculations and revisions, which supports traceability and continuous improvement. It helps team members understand why choices were made and allows later review or auditing of the design process.

Question 28Engineering fundamentals and the engineering process

A simply supported beam of span 6 m carries a uniformly distributed load of 4 kN/m over its entire length. What is the magnitude of the vertical reaction at each support?

  1. 12 kN Correct answer.
  2. 24 kN
  3. 4 kN
  4. 6 kN

Explanation

The total load is 4 kN/m × 6 m = 24 kN. By symmetry, each of the two supports carries half the total load, so the reaction at each support is 12 kN.

Question 29Engineering fundamentals and the engineering process

A manufacturer wants to compare the variability of two production lines making the same part. Line A has a mean diameter of 20.0 mm and a standard deviation of 0.10 mm; Line B has a mean of 20.0 mm and a standard deviation of 0.25 mm. Which statement best interprets these statistics?

  1. Line A has a larger standard deviation, so it produces more varied parts.
  2. Line A is more consistent because its smaller standard deviation indicates less spread around the mean. Correct answer.
  3. Both lines have identical consistency because their means are equal.
  4. Line B is more consistent because its larger standard deviation shows greater control.

Explanation

Standard deviation measures the spread of measurements around the mean. A smaller standard deviation, such as Line A's 0.10 mm, indicates that the parts are more tightly clustered around the target diameter, so the process is more consistent.

Question 30Engineering fundamentals and the engineering process

An engineer is selecting a material for a bicycle frame that must be stiff, light and resistant to fatigue. The candidate materials have the following properties: Material W: high Young's modulus, low density, high fatigue strength; Material X: low Young's modulus, low density, low fatigue strength; Material Y: high Young's modulus, high density, high fatigue strength; Material Z: low Young's modulus, high density, low fatigue strength. Which material best satisfies all three requirements?

  1. Material Z
  2. Material Y
  3. Material X
  4. Material W Correct answer.

Explanation

Material W combines high stiffness (high Young's modulus), low weight (low density) and good fatigue resistance (high fatigue strength), meeting all three requirements. The other materials fail at least one criterion, such as being too heavy or too flexible.

Question 31Engineering materials and their properties

Which property describes a material's ability to resist being permanently indented or scratched?

  1. Elasticity
  2. Hardness Correct answer.
  3. Toughness
  4. Ductility

Explanation

Hardness measures resistance to localised plastic deformation such as indentation, scratching or abrasion. Ductility concerns stretching, toughness concerns energy absorption before fracture, and elasticity concerns reversible deformation, so none of these describe surface indentation resistance.

Question 32Engineering materials and their properties

A tensile test specimen is loaded and its extension recorded until it breaks. Which quantity is found by dividing the maximum load by the original cross-sectional area?

  1. Elongation at fracture
  2. Tensile strength Correct answer.
  3. Young's modulus
  4. Yield strain

Explanation

Tensile strength is the peak stress reached on the engineering stress-strain curve, calculated as maximum load divided by the original cross-sectional area. Young's modulus comes from the slope of the elastic region, while elongation and yield strain are strain measures, not stresses.

Question 33Engineering materials and their properties

Which class of engineering material is characterised by a crystalline lattice in which delocalised electrons allow high electrical and thermal conductivity?

  1. Engineering ceramic
  2. Thermoplastic polymer
  3. Metal Correct answer.
  4. Elastomer

Explanation

Metals have a regular lattice of positive ions surrounded by a sea of delocalised valence electrons, which carry charge and heat efficiently. Polymers and ceramics lack this free-electron structure, so they are generally electrical and thermal insulators.

Question 34Engineering materials and their properties

A component must return to its original dimensions when a load is removed. Which property must the design rely on?

  1. Elasticity Correct answer.
  2. Creep resistance
  3. Malleability
  4. Plasticity

Explanation

Elasticity is the property that allows a material to recover its original shape and size when the applied stress is removed. Plasticity and malleability involve permanent deformation, and creep resistance concerns slow deformation under sustained load.

Question 35Engineering materials and their properties

Which material is a thermosetting polymer?

  1. Polyvinyl chloride
  2. Epoxy resin Correct answer.
  3. Polyethylene
  4. Polypropylene

Explanation

Epoxy resins cure by forming permanent cross-links between polymer chains, so they cannot be remelted and reshaped. Polyethylene, PVC and polypropylene are thermoplastics that soften on heating because their chains are not chemically cross-linked.

Question 36Engineering materials and their properties

A steel shaft is required to transmit torque without permanent twisting. Which property is the most direct measure of its resistance to elastic shear deformation?

  1. Density
  2. Poisson's ratio
  3. Shear modulus Correct answer.
  4. Thermal expansion coefficient

Explanation

The shear modulus is the ratio of shear stress to shear strain in the elastic region, so it directly quantifies resistance to elastic shear deformation under torsion. Poisson's ratio, density and thermal expansion describe lateral contraction, mass and dimensional change with temperature.

Question 37Engineering materials and their properties

Which statement correctly distinguishes a thermosetting polymer from a thermoplastic?

  1. Thermosets can be repeatedly remelted and reshaped after curing.
  2. Thermosets are always more ductile than thermoplastics at room temperature.
  3. Thermosets have permanent covalent cross-links that prevent remelting. Correct answer.
  4. Thermosets consist of linear chains that slide past one another when heated.

Explanation

During curing, thermosetting polymers develop a three-dimensional network of permanent covalent cross-links, so heating cannot separate the chains and the material degrades rather than melting. Thermoplastics have linear or branched chains held by weaker secondary forces, allowing repeated softening and reshaping.

Question 38Engineering materials and their properties

Why are ceramics typically poor conductors of electricity at room temperature?

  1. They contain large numbers of free delocalised electrons.
  2. They have very low melting temperatures.
  3. Their valence electrons are tightly held in ionic or covalent bonds. Correct answer.
  4. Their atoms are arranged in an amorphous random structure.

Explanation

In ceramics, electrons are localised in strong ionic or covalent bonds, so there are few mobile charge carriers to support a current. Metals conduct because their delocalised electrons are free to move through the lattice.

Question 39Engineering materials and their properties

A material's engineering stress-strain curve shows a linear region ending at a stress of 240 MPa and a strain of 0.0012. What is the elastic modulus?

  1. 20 GPa
  2. 2000 GPa
  3. 2.0 GPa
  4. 200 GPa Correct answer.

Explanation

Elastic modulus is stress divided by strain in the linear elastic region: 240 MPa divided by 0.0012 equals 200 000 MPa, or 200 GPa. The calculation uses the gradient of the straight portion of the curve.

Question 40Engineering materials and their properties

A metal with a face-centred cubic crystal structure is deformed plastically. Which mechanism is primarily responsible for this permanent deformation?

  1. Migration of substitutional atoms through the lattice
  2. Formation of covalent cross-links between grains
  3. Reversible stretching of atomic bonds
  4. Slip of dislocations along crystallographic planes Correct answer.

Explanation

Plastic deformation in crystalline metals occurs mainly by the movement of dislocations along close-packed slip planes and directions. Atomic diffusion is too slow at room temperature, and bond stretching is elastic and reversible.

Question 41Engineering materials and their properties

A low-carbon steel and a high-carbon steel are compared. Which change is expected as carbon content increases?

  1. Tensile strength and hardness decrease while ductility increases
  2. Tensile strength and hardness increase while ductility decreases Correct answer.
  3. Tensile strength increases while hardness stays constant
  4. Ductility increases while yield strength stays constant

Explanation

Increasing carbon content raises the amount of hard cementite phase, which impedes dislocation motion and so increases strength and hardness. The same restriction on plastic flow reduces elongation, so ductility falls.

Question 42Engineering materials and their properties

Which feature of a tensile stress-strain curve indicates the onset of permanent deformation?

  1. The yield point Correct answer.
  2. The proportional limit at zero stress
  3. The fracture point
  4. The ultimate tensile strength point

Explanation

The yield point marks the stress at which the material stops behaving elastically and begins to deform permanently. Below yield, deformation is recoverable; ultimate strength and fracture occur at larger strains after substantial plastic flow.

Question 43Engineering materials and their properties

A component made from a polymer is exposed to a constant load for several years at elevated temperature. Which failure mode is most likely to be of concern?

  1. Hydrogen embrittlement
  2. Brittle cleavage fracture
  3. Fatigue failure from cyclic loading
  4. Creep deformation Correct answer.

Explanation

Creep is time-dependent permanent deformation under sustained stress, and polymers are especially susceptible near or above their glass transition temperature. Fatigue requires cyclic loading, while cleavage and hydrogen embrittlement are characteristic of metals.

Question 44Engineering materials and their properties

Which property best describes a material's ability to absorb energy and deform plastically before fracturing?

  1. Toughness Correct answer.
  2. Elastic limit
  3. Stiffness
  4. Hardness

Explanation

Toughness is the energy a material absorbs up to fracture, combining strength and ductility, and is represented by the area under the stress-strain curve. Hardness resists indentation, stiffness resists elastic deformation, and the elastic limit bounds recoverable strain.

Question 45Engineering materials and their properties

A brass component is to be formed into a complex shape by cold pressing without cracking. Which combination of properties is most desirable?

  1. High brittleness and high stiffness
  2. High creep resistance and low toughness
  3. High hardness and low elongation
  4. High ductility and low yield strength Correct answer.

Explanation

Cold forming requires the material to flow plastically without fracture, so high ductility and a relatively low yield strength allow it to conform to the die shape. Hard, brittle or stiff materials resist flow and tend to crack during pressing.

Question 46Engineering materials and their properties

Which statement about the density of engineering materials is correct?

  1. Density has no influence on the specific strength of a material.
  2. Ceramics generally have much higher density than steels because of their strong bonds.
  3. Aluminium alloys have a lower density than steels and are therefore attractive where weight saving matters. Correct answer.
  4. Polymers have higher density than metals because their chains are closely packed.

Explanation

Aluminium alloys have a density near 2700 kg/m3 compared with roughly 7800 kg/m3 for steel, so replacing steel with aluminium reduces mass for a given volume. Specific strength, the ratio of strength to density, therefore depends strongly on density.

Question 47Engineering materials and their properties

A steel bracket is to be protected from corrosion in a marine atmosphere. Which material property most strongly determines whether galvanic corrosion will occur when it is bolted to an aluminium plate?

  1. The melting point of the two metals
  2. The thermal conductivity of the two metals
  3. The hardness of the two metals
  4. The position of the two metals in the galvanic series Correct answer.

Explanation

Galvanic corrosion occurs when two dissimilar metals in electrical contact are exposed to an electrolyte, and its severity depends on how far apart they sit in the galvanic series. The metal higher in the series becomes anodic and corrodes, so the potential difference drives the reaction.

Question 48Engineering materials and their properties

A material is described as having a high modulus of resilience. Which quantity does this refer to?

  1. The total area under the entire stress-strain curve
  2. The area under the elastic portion of the stress-strain curve Correct answer.
  3. The strain remaining after unloading
  4. The stress at which the specimen fractures

Explanation

The modulus of resilience is the strain energy stored per unit volume within the elastic limit, equal to the area under the elastic part of the stress-strain curve. The total area under the curve to fracture is toughness, while fracture stress and residual strain describe other features.

Question 49Engineering materials and their properties

Which type of bonding is responsible for the high melting temperature and brittleness of many engineering ceramics such as alumina?

  1. Metallic bonding
  2. Weak van der Waals forces
  3. Hydrogen bonding between long chains
  4. Ionic and covalent bonding Correct answer.

Explanation

Alumina and similar ceramics are held together by strong ionic and covalent bonds, which require large amounts of energy to break and so give high melting points. These directional, rigid bonds also restrict dislocation movement, making the material brittle rather than ductile.

Question 50Engineering materials and their properties

A tensile specimen of initial length 50 mm is pulled to a length of 60 mm at fracture. What is the percentage elongation?

  1. 120 percent
  2. 20 percent Correct answer.
  3. 16.7 percent
  4. 10 percent

Explanation

Percentage elongation is the change in length divided by the original length, multiplied by 100: 10 mm divided by 50 mm gives 0.20, or 20 percent. This value is a standard measure of ductility.