Electrotechnology 2025 HSC exam pack

Students should:

• read the question carefully to ensure that they do not miss important components of the question
• have a clear understanding of key words in the question and recognise the intent of the question and its requirements
• use the first page of the extended response answer booklet to develop a plan to assist in the logical sequencing of information
• engage with what the question is asking rather than presenting a pre-prepared response
• relate to the question throughout the response rather than just at the beginning
• ensure each extended response answer is completed in a separate writing booklet
• demonstrate knowledge and understanding of HSC content from the syllabus
• communicate ideas and information using relevant workplace examples and industry terminology
• be prepared to address a range of industry issues
• demonstrate knowledge of employability skills relevant to various situations
• include relevant annotations when providing a diagram
• present a logical and cohesive response that answers the question
• review their response to ensure that it addresses the question requirements.

Question 16 (a)

In better responses, students were able to:

• identify the modes of the drill as, ‘rotary’, ‘hammer’ and ‘rotary and hammer’.

Areas for students to improve include:

• identifying all the different modes of a rotary hammer drill.

Question 16 (b)

In better responses, students were able to:

• demonstrate understanding of the safety removal methods of the affected worker from the live drill
• describe the check for danger from electrical shock before attempting to rescue the worker from the live drill.

Areas for students to improve include:

• describing the use of an insulated instrument to either remove the affected worker or the drill
• describing the check for any dangers before attempting to rescue the worker from the live drill.

Question 17 (a)

In better responses, students were able to:

• identify the need to use a hammer drill when drilling into a concrete wall
• demonstrate understanding of the need to use a masonry or tungsten tip drill bit when drilling into a concrete wall
• identify the need to use suitable bolts, chemical fixings or wall plugs when fixing into a concrete wall.

Areas for students to improve include:

• demonstrating understanding of the hammer function on power drills
• identifying different types of drill bits and their application, for example, masonry drill bits
• demonstrating understanding of different types of fixings and their application, for example, suitable bolts and chemical fixing.

Question 17 (b)

In better responses, students were able to:

• identify the tools and materials required to fix the metal bracket in the wall, that is, suitable bolts, masonry drill, drill bits, level and tape measure
• demonstrate understanding of the appropriate method required to fix the bracket and clearly state the processes involved
• identify the need to barricade the working area for safety purposes
• identify suitable personal protection equipment (PPE) as safety glasses, hearing protection and a dust mask.

Areas for students to improve include:

• demonstrating understanding of the processes of fixing metal brackets and the range of tools required, for example, drilling into a concrete wall requires using a masonry drill and drill bit
• demonstrating understanding of the materials required for the process, for example, suitable bolts or equivalent fittings
• demonstrating understanding of the need to measure and mark out the fixing holes before drilling
• recognising the need for correct PPE to be used.

Question 18

In better responses, students were able to:

• demonstrate understanding that poor business practices can cause loss of reputation and loss of income
• explain that businesses might be liable for prosecution for injuries received due to poor business practices and could incur fines.

Areas for students to improve include:

• identifying a variety of poor business practices
• expanding on reasoning behind poor work practices
• demonstrating understanding that errors in work undertaken can incur a financial cost that needs to be rectified.

Question 19 (a)

In better responses, students were able to:

• identify the two symbols as representing a 2-way switch and a main switchboard.

Areas for students to improve include:

• demonstrating understanding of symbols used in electrotechnology plans
• using correct industry terminology.

Question 19 (b)

In better responses, students were able to:

• convert a circuit diagram to a wiring diagram
• show a fuse connected for circuit protection correctly
• demonstrate understanding that an active conductor must be switched, and can be looped at the light or the switch
• locate the active, neutral and earth connections at the batten holders correctly
• identify that the lamps are connected in parallel.

Areas for students to improve include:

• identifying that a fuse or equivalent is required for circuit protection
• demonstrating understanding of how 2-way switching works
• demonstrating understanding of the difference between a circuit diagram and a wiring diagram
• demonstrating understanding of how to convert a circuit diagram to a wiring diagram
• demonstrating understanding that active, neutral and earth conductors are connected at light switches and light fittings, not in midair.

Question 20 (a)

In better responses, students were able to:

• identify that the current reduces and the voltage reduces.

Areas for students to improve include:

• demonstrating understanding that if resistance increases, the current across the lamp will reduce and the voltage across the lamp will reduce.

Question 20 (b)

In better responses, students were able to:

• calculate the circuit resistance with the correct units, that is, ohms (Ω)
• show working and use the correct equations, for example, R=V/I.

Areas for students to improve include:

• demonstrating understanding of engineering notation
• demonstrating understanding of how to transpose equations
• using the correct units, that is, ohms (Ω)
• demonstrating understanding of the relationship between the supply voltage and current flow to calculate circuit resistance.

Question 20 (c)

In better responses, students were able to:

• calculate the resistance of the lamp and apply Ohm’s Law
• demonstrate understanding that if the voltage is halved in the lamp, the current will be halved
• show their working and use the correct equations
• calculate the current with the correct units, that is, amperes (A).

Areas for students to improve include:

• using the correct units, that is, amperes (A)
• demonstrating understanding of power equations
• demonstrating understanding of Ohm’s Law
• addressing each part of the question separately.

Question 20 (d)

In better responses, students were able to:

• address each part of the question separately
• find the total resistance using Ohm’s Law
• find the resistance of the lamp using a power equation
• demonstrate understanding of series resistances.

Areas for students to improve include:

• using the correct units, that is, ohms (Ω)
• demonstrating understanding of the relationship between the supply voltage and current flow to calculate circuit resistance
• addressing each part of the question separately.

Question 20 (e)

In better responses, students were able to:

• address each part of the question separately
• find the resistance of the lamp using a power equation
• find the current using Ohm’s Law
• use the correct units, that is, watts (W).

Areas for students to improve include:

• addressing each part of the question separately
• using the correct units, that is, watts (W)
• demonstrating understanding of the relationship between the resistance of the lamp and the voltage to calculate the power dissipated by the lamp.

Question 21 (a)

In better responses, students were able to:

• include appropriate work health and safety (WHS) documentation in the work schedule, for example, conducting a risk assessment prior to commencement of work
• outline time frames and documentation required for work to take place and be completed
• include the use of site plans.

Areas for students to improve include:

• demonstrating understanding of the range of documentation required prior to commencing work, for example, site plans, safe work method statement (SWMS) and product specifications
• answering parts (a) and (b) separately.

Question 21 (b)

In better responses, students were able to:

• identify traffic management control measures required, for example, barricades, signage and safety personnel diverting the traffic and pedestrians around the worksite
• include appropriate WHS strategies for the work schedule, for example, conducting a risk assessment prior to commencement of work
• break the installation down into various stages and tasks, for example, risk assessment, establishment of the work zone, excavation and installation of cables, remediation of trenches and installing slabs for charging stations to be installed onto, isolation of electricity and lock out, installation and connection of charging stations, testing and commissioning of electrical circuits at the completion of the installation.

Areas for students to improve include:

• breaking the installation down into various stages and tasks, for example, testing and commissioning of electrical circuits is required at the completion of the installation
• providing examples of work activities, for example, underground cabling requiring specialist excavation personnel and machinery
• answering parts (a) and (b) separately. 

Question 22

In better responses, students were able to:

• provide detailed references to both long- and short-term considerations, for example, use building orientation to minimise energy consumption in winter and summer, install solar panels on the roof and a battery system set up to minimise consumption from the grid
• explain relevant matters to be considered in sustainable and energy efficient design and construction of medium density housing using industry terminology.

Areas for students to improve include:

• expanding on matters to be considered in sustainable, energy efficient design and construction and providing relevant examples, for example, double glazed windows, sky lights, insulating walls
• demonstrating understanding of the difference between long- and short-term needs to be considered
• demonstrating understanding of the difference between sustainability and energy efficiency.