Engineering Studies 2023 HSC exam pack

Students should:

• read the question carefully to ensure that they do not miss important components of the question
• avoid simply re-stating the question in their response
• have a clear understanding of key terminology in the question and recognise the intent of the question and its requirements
• engage with any stimulus material provided and refer to it in the response
• communicate ideas and information using relevant examples
• expect to perform some mathematical functions, interpret data/graphs/tables and assess information for accuracy, reliability and/or validity
• consider using graphical solutions if appropriate
• review their response to ensure that it addresses the question requirements
• include all working in calculation responses, and set these out in a logical manner
• be familiar with relevant engineering terminology and use it correctly to enhance their answers
• use correct materials terminology when speaking about engineering materials, for example, most uses of aluminium are in alloyed form so students should be writing ‘aluminium alloys’ to make it clear they understand aluminium is being used in an alloyed form
• calculate the area of circle using the formula πd²/4, because in Engineering Studies using diameters as opposed to radii in calculation problems is more common
• ensure the use of appropriate drawing equipment to maximise their performance all drawing questions across the examination.

Question 21

In better responses, students were able to:

• associate a specific example such as a 3D CAD model with a dedicated aeronautical engineering use (a)
• state why or how collaboration is advantageous in the process of completing the engineering report using examples to show cause and effect (b)
• display clear evidence of an isometric perspective showing accurate overall shape and a reflection of the features such as the holes, the web and the lip offset (c)
• accurately draw and clearly label a network of entangled polymer chains that were connected with covalently bonded cross links (d)
• describe appropriate features and/or characteristics of the thermosetting polymer (d).

Areas for students to improve include:

• using specific and current examples of computer graphics in aeronautical engineering applications (a)
• demonstrating an understanding that completing the engineering report refers to all stages of the report and not just the final hand in stage (b)
• recognising prominent features in the orthogonal drawing given and transferring that information accurately to a proportional isometric sketch (c)
• understanding the difference between an isometric drawing and other types of pictorial drawings such as oblique, perspective and planometric (c)
• describing features and characteristics of their thermosetting polymer microstructure showing entangled polymer chains with primary bonds as cross linking (d)
• developing an understanding of the microstructure of polymers chains and amorphous materials (d).

Question 22

In better responses, students were able to:

• identify that copper chromium arsenate (CCA) solution is toxic, carcinogenic or poisonous and therefore harmful to children on playground equipment (ai)
• identify the potential environmental impacts of CCA through both the leeching of the material, toxic fumes released when burnt, or another disposal (ai)
• use prior knowledge regarding other materials that have been used in playgrounds (ai)
• separate chromium and copper as being metals/alloys (ai)
• identify a suitable specific material and justify their choice citing properties of materials including ultraviolet (UV) resistance (aii)
• correctly calculate both reactions using a correct method and give correct sense and directions (bi)    
• correctly calculate moments, direction of the moments and calculate the reaction (bi)    
• understand correct and appropriate lever arms (bi)   
• produce the labelled shear force (SF) and bending moment (BM) diagrams from the previous calculations using an appropriate scale (bii)
• produce a BM diagram by calculating either the area under the SF diagram or by calculating the BM at each point (bii)   
• recognise the forces and moments were in balance and would return to zero (bii).

Areas for students to improve include:

• identifying dangers in playground equipment (ai)
• developing an understanding of metals and alloys including chromium and copper (ai)
• engaging with a larger range of structural and non-structural materials and their properties (aii)
• understanding that the weather refers to properties of materials exposed to the elements (aii)
• being more specific in suggesting materials for the application (aii)
• understanding the differences and working characteristics between thermosetting and thermosoftening / thermoplastic / thermoforming polymers (aii)   
• plotting the point loads from the image onto the SF diagram and projecting down from the SF to BM diagram (bii)   
• correctly labelling key points on the SF and BM diagrams (bii)
• using an appropriate scale (bii)
• identifying an appropriate point about which to take moments (bii)    
• producing the labelled SF and BM diagrams from previous calculations (bii)   
• produce a BM diagram by calculating either the area under the SF diagram or by calculating the BM at each point (bii)    
• using correct units and calculations, including methods of checking, and the closure of SF (bii).

Question 23

In better responses, students were able to:

• recall common electrical symbols, indicate correct symbols for light in light emitting diode (LED) and light dependent resistor (LDR), and correctly label an NPN transistor (a)
• provide multiple responsibilities for the telecommunications engineer with respects to security
• provide a correct example of an instance where insulation is used in telecommunications. For example, polymer coating around CAT5 and coaxial cables, polymer housing for telecommunication devices such as a mobile phone (c)
• correctly identify the need for insulation around optical fibres (c)
• engage with the stimulus to explain attenuation of 5G with regards to 4G (d).  

Areas for students to improve include:

• ensuring that outdated symbols are not used, such as the jagged line symbol for a resistor (a)
• using correct terminology regarding security issues (b)
• providing examples where needed that address the question (c)
• understanding that when asked to refer to the diagram it requires some engagement with the diagram (d).  

Question 24

In better responses, students were able to:

• compare relevant properties of each material such as tensile and compressive strength, durability, malleability, and ductility (a)
• understand that both timber and steel have good strength to weight ratio but steel is superior (a)
• understand that the required grain structures related to the weld metal, and accurately sketch, locate and label each of the three grain types (b)
• appreciate that columnar grains extend from the parent metal similar to an as-cast microstructure (b)
• apply the formula for potential energy and kinetic energy and substitute in values for each, and show an understanding that potential energy could be converted to kinetic energy and then converted back into potential energy (c)
• explain the purpose of the NAND gate in the schematic (di)
• demonstrate an understanding that all the conditions had to be achieved through the preceding gates before the NAND gate turned off the warning light, indicating that the ride could commence (di)
• clearly understand the purpose of a truth table to demonstrate all possible inputs and outputs for the specified schematic (dii)
• ensure each row of the truth table had to be unique and not simply be repeated (dii).

Areas for students to improve include:

• comparing similarities and differences for each material and understanding that some properties, such as hardness, are not relevant for comparison (a)
• focusing on the properties of the material rather than simply describing the stimulus images (a)
• understanding how various grain types arise, such as columnar and equiaxed grains, and chill crystals in a heat affected zone and then being able to represent these graphically (b)
• demonstrating knowledge that the roller coaster could have both kinetic and potential energy at the same time and understanding the principle of the conservation of energy is fundamental to determining the answer to this question (c)
• understanding that the schematic/circuit does not function as a power supply to the braking system (di)
• addressing the purpose of the NAND gate in relation to the schematic (di)
• gaining a better understanding of the range of possible inputs for a truth table (dii)
• understanding the truth table for each logic gate and engaging with the stimulus material in the question (dii).

Question 25

In better responses, students were able to:

• demonstrate understanding of the process of compression moulding to produce polymer, elastomer and composite materials from a solid transformed under heat and external force (a)
• explain how semiconductors enable transistors to function as a switch or an amplifier or how transistor functions enable miniaturisation and improved efficiency in electronics (b)
• outline trilateration or the process of determining locations by measurement of distances using the geometry and/or calculations based on the time a signal is sent from the satellite and the time it is received by the GPS device (c)
• determine the point of concurrency of a three-force load condition and correctly determine the angle of static friction or use an analytical method (d).

Areas for students to improve include:

• ensuring that their explanation relates cause and effect and provides at least two functions (b)
• understanding that the satellites only transmit signal, that at least three satellites are required and that the calculation is performed by the GPS device (c)
• using graphical mechanics methods to solve engineering problems (d)
• understanding how to determine the angle of static friction and then understanding its relationship with the coefficient of friction (d).

Question 26

In better responses, students were able to:

• recognise that the shear area here is the perimeter of the shape multiplied by the thickness of the plate, and then use that to determine the force required (a)
• correctly use the formula for the circumference of a circle to help determine the complex perimeter of the outline (a)
• describe an implication for both the individual engineer and the company (b)
• break the description into two clear implications (b)
• recognise member EF and the reaction at the right support are collinear, then realise member GF was redundant because of this. Hence determining the magnitude and nature of the internal reaction in EF by observation of this situation (c)
• show an understanding of the method of sections by summing the vertical forces after indicating a cutting plane through CD, CH and HI. Additionally recognising that analysing the right-hand section of the truss was the best way to determine CH (c).

Areas for students to improve include:

• understanding the difference between shear stress and compressive stress (a)
• understanding that, in this case, the shear area is the perimeter of the cutout multiplied by the thickness (a)
• knowing how to use SI unit prefixes correctly to ensure the correct magnitude of units (a)
• stating if the implication described or outlined was for the engineer or company (b)
• providing better descriptions of implications to both the individual engineer and the company (b)
• avoiding stating an implication without describing it (b)
• understanding the impact of redundant members in truss analysis (c)
• understanding how to apply the equations of equilibrium to truss analysis (c)
• applying the method of sections to determine the magnitude and nature of the force in a member of a truss (c).

Question 27

In better responses, students were able to:

• demonstrate knowledge of composite materials used in aircraft construction (a)
• relate characteristics and features of composites to specific uses in aircraft construction (a)
• discuss the benefits and drawbacks of specific composite examples used in aircraft construction (a)
• graphically represent an assembly of components in a sectioned front view to AS1100 (b)
• apply AS1100 standards for representing threaded components correctly (b)
• apply AS1100 standards for sectioning correctly (b)
• convert measurements using a scale correctly (b)
• use given features in the working space to position components of the assembly correctly (b)
• position the cutting plane in sectional view correctly (b).

Areas for students to improve include:

• understanding the range of composites used in aircraft construction (a)
• differentiating between composites and alloys used in aircraft construction (a)
• providing specific reasons why composites are used in aircraft construction (a)
• using correct conventions to AS1100 in the representation of threaded components and line types (b)
• using correct sectioning standards including threaded components in assembly drawings (b)
• ensuring components are assembled clearly and correctly (b)
• accurately measuring sizes and constructing vertical and horizontal lines (b).