Practical and viva marks are the most predictable part of a GTU semester, yet students lose them every year — usually because they treated the practical as a formality and never opened the journal before the exam week. The preparation needed is small and specific. This guide covers the structure of a typical practical exam and the questions that come up again and again in the oral.

How a practical exam usually unfolds

1. The journal / file — submitted and checked first. A complete, neatly written journal with all experiments, readings and conclusions sets the tone for the rest.
2. The experiment — you perform or demonstrate a set experiment, often one from the lab manual.
3. The written/working part — calculations, observations, or a short design task.
4. The viva — an oral round where the examiner probes your understanding of what you just did and the theory behind it.

The journal is not busywork

The journal is the examiner's first impression and often carries its own marks. Complete it while the practicals are fresh, not in a rush at the end of term. For each experiment, make sure it has:

• Aim and apparatus/equipment listed clearly.
• Theory in a few lines — the principle the experiment demonstrates.
• Procedure in numbered steps.
• Observation table with correct units and headers.
• Calculations shown step by step, and a result with units.
• Conclusion — one or two lines linking the result to the theory.

What examiners actually ask in the viva

Most viva questions cluster into a few predictable families. Prepare these for each experiment and you will cover the majority of the oral:

Question family	What they are checking
"What is the principle behind this experiment?"	That you understand why it works, not just how to run it.
"Why did you take this reading / why this value?"	Whether you understand the variables and their expected ranges.
"What are the possible sources of error?"	Practical awareness — instrument limits, parallax, heat loss, human error.
"What happens if you change X?"	Whether you can reason about the setup instead of memorising it.
"Where is this used in industry / real life?"	Application, the higher Bloom's-taxonomy level.
"Define this term / component."	Basic vocabulary from the theory of the experiment.

How to prepare efficiently

1. Make one question sheet per experiment. Write the aim, the principle in two lines, and the five questions above with your own answers.
2. Know your apparatus names. A surprising number of viva marks are lost to not knowing what a piece of equipment is called or what it measures.
3. Rehearse out loud. Answering in your head is not the same as speaking to an examiner. Say the principle out loud once per experiment.
4. Connect each experiment to its theory unit in your syllabus, so the oral links back to concepts you already studied.
5. Read the last few questions of your journal before you walk in — they are the freshest in your mind and often the ones asked first.

Practical marks reward consistency

Unlike theory, practical assessment often happens through the whole term — attendance, timely journals, lab performance and the final exam together. Turning up prepared, finishing experiments in the allotted time, and keeping your journal current is itself most of the work. The viva rewards the same thing the theory exam does: understanding the principle, expressed in your own words.

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