IB Physics Engineering exam tips

Studying IB Physics Option B Engineering Physics? If so, the 10 IB Physics Engineering Exam Tips below have been written specifically for you. We’re sharing this advice from our study guide Physics Option B Engineering Physics Standard and Higher Level written by Hugh Duncan to help you avoid making these common errors come exam time. Whether you are just starting on your IB journey or fast approaching your exams, the advice below can help to ensure you approach your IB Physics studies with success in mind and maximise your marks.

IB Physics Option B Engineering Mistakes to Avoid

1. Forgetting units, or recording the wrong units. This is a continual cause for loss of marks. Ratios have no units, but otherwise all other quantities do. If you cannot remember them, they can be found by putting in the units of the individual quantities. E.g. Stoke’s Law F = 6πηrv, and you want the units of η. So η = F/6πrv; if r is in m, v in ms^-1 and F and N (and N from F = ma = kgms^-2) which makes η = kgms^-2/m.ms^-1 = kgms^-1s^-1.
2. Not converting quantities into the correct units. Unless otherwise stated, all units should be SI units (kg, s, m, etc.). Often measurements are given in cm or g so the student must check whether they need to be changed before calculating.
3. Not drawing diagrams or drawing them badly. A diagram can make a problem easier to understand and if an examiner asks for a sketch, then put in the effort it deserves. It is an insult to not use a sharp pencil and ruler and label clearly.
4. Not showing your work. Usually working out is requested and marks are removed if none is shown. It is still possible to score points by showing working, even if the final answer is wrong.
5. Not rounding answers. Remember that the final answer has as many significant figures as the least significant number in the problem. IB does allow one more or one less, but best not to get sloppy!
6. Confusing changes to a gas. There are three gas laws, Boyles, Charles and the pressure law. Don’t get them mixed up. There are similar sounding changes made to a gas, e.g. isobaric, isothermal, isochoric and so on. Treat it as a spelling test of French irregular verbs and learn what each one does.
7. Not using Kelvin. Units of volume and pressure are not critical in the gas laws, but temp in °C must be converted to kelvin K = °C + 273.
8. Swapping around or reversing the terms in the first law of thermodynamics. Remember work done by the gas is positive; work done on the gas is negative.
9. Not understanding the second law. Yes it is an unusual concept but a very important one. Several versions are given in the Physics Option B Engineering Physics Standard and Higher Level study guide; other books will give alternative examples. In a nutshell, no process can convert 100% heat to mechanical energy.
10. Using vague terms instead of physics terms. It is important to give answers in terms of Newton’s laws and the strict definitions offered.

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For more IB Physics help

This list is a starting point for you to refine your IB Phyiscs revision. If you are already following the tips listed above, you're on your way to doing your best in your IB exams. If some of the tips are new to you or you haven't quite integrated them into your IB Physics Engineering work then be sure to start straight away. Following these tips before your IB exams will make them second nature and you'll have a better chance of not losing valuable marks to common errors.

For more IB Physics advice and tips, be sure to visit our IB Physics resource page where we have articles, study tools, and our full rnage of IB Physics study guides.