Practical / Project Work and Viva Voce
What the exam tests
Practical work and viva voce assesses project planning, observation, measurement, tool use, safety and explanation of results. You may be asked to describe a project, justify a diagnosis or answer questions about a procedure you performed.
Core rules and concepts
- A project report should state the aim, apparatus, procedure, observations, calculations, result and conclusion.
- Record raw readings with units and instrument least count.
- Take repeat readings and check zero error.
- Follow safety rules and use the correct tool for the job.
- In viva, explain why a step was done, not just what was done.
- Compare results with specifications and state limitations.
Worked example
A brake pad inspection records a new pad thickness of 12 mm and a worn thickness of 4 mm after 40,000 km. Wear = 12 - 4 = 8 mm. Wear rate = 8/40,000 = 0.0002 mm/km, or 0.2 mm per 1,000 km. The service limit is 2 mm, so remaining wear allowance is 4 - 2 = 2 mm. Estimated remaining life = 2/0.0002 = 10,000 km. The estimate assumes the same wear rate and no uneven wear.
Traps that cost marks
- Recording readings without units or least count.
- Presenting a conclusion without observations.
- Demonstrating a procedure without safety precautions.
- Ignoring uneven wear or a scoring/damage condition.