Exam technique
Technique cannot replace physics, but poor technique loses marks that knowledge had already earned. Everything below follows from the published format and marking, and none of it depends on knowing any specific examination question.
120 minutes across 40 stems averages 3 minutes per five-statement question, or roughly 36 seconds per statement. Treat that as a checkpoint benchmark, not a timer you must obey on every question.
With no negative marking, an unanswered item is a guaranteed zero while a considered judgement has real expected value — and partial knowledge usually makes it better than chance. Blank statements are the most avoidable loss in the paper.
There is no requirement for a stem to contain a mixture of True and False answers. Changing a well-reasoned answer because four items already read True is a way of converting knowledge into a guess. Judge each item on its own physics.
Read the stem once for the scenario, then treat each item as a standalone claim to be judged against that scenario. The categories below cover most of what the paper asks you to discriminate.
Words such as always, never, all or only make a statement fail on a single exception. Test the claim against the edge case you know before accepting it, but do not treat an absolute as automatically false — some physical rules genuinely hold without exception.
Decide the direction first: as this increases, does that rise or fall? Many errors are correct physics with the sign reversed. Say the relationship aloud in your head before marking.
Distinguish linear, inverse, square and inverse-square relationships, and whether the stated dependence holds only when other parameters are fixed. A relationship that is true 'all else equal' can be false when the statement changes two variables.
Check that the quantity named matches the unit and the thing being measured — activity versus dose, absorbed versus equivalent versus effective dose, index quantities versus patient dose.
Separate physical principle from local policy. Statements about justification, optimisation and limitation, or about field and implant hazards, should be judged on established principle, not on how your department happens to work.
Noise, resolution, contrast, dose and acquisition time move together. A statement claiming an improvement with no cost is worth extra scrutiny; so is one that ignores a modulation or reconstruction technique that changes the usual relationship.
Classify the failure before you correct it. The class of error determines what repair work will actually help.
| Error type | What happened | Repair |
|---|---|---|
| Fact recall | You did not know the underlying value, definition or mechanism. | Add the single fact to the log and re-test it with fresh statements. |
| Sign or direction | You knew the variables but reversed the effect. | Rewrite the relationship as an explicit 'if X increases, Y ...' sentence. |
| Unit or quantity | You confused two related quantities or their units. | Write both quantities side by side with what each does and does not represent. |
| Proportionality | You knew the direction but not the form or the conditions. | Note the dependence and the parameters that must be held constant. |
| Application | You knew the principle but misapplied it to the scenario in the stem. | Re-read the stem's conditions and identify the clause you overlooked. |
Technique only becomes automatic under realistic conditions. Start with five stems, then rehearse pacing over an exam-length paper.
Physics revision guides
The 40-stem, 200-item paper, timing, marking, current topic distribution and official candidate guidance.
How modified Angoff and Hofstee standard setting work, and why there is no permanent fixed percentage.
A practical route from concept learning and topic blocks to mixed practice, error repair and full mocks.
Use targeted stems and exam-length mocks for different jobs, then convert each result into focused recovery work.
Matter and Radiation
FRCR Physics matter and radiation revision: atomic structure, photon energy, attenuation, interactions, inverse square law and common True/False traps.
Radiography and Fluoroscopy
FRCR Physics radiography and fluoroscopy revision: X-ray production, detectors, grids, AEC, image quality, fluoroscopic dose and common exam traps.
Radionuclide Imaging
FRCR Physics radionuclide revision: decay, gamma cameras, collimators, SPECT, PET, counting statistics, corrections, dose and common True/False traps.
Radiation Safety
FRCR Physics radiation safety revision: dose quantities, biological effects, IRR17, IR(ME)R 2017, duty holders, optimisation, DRLs and common traps.
Ultrasound
FRCR Physics ultrasound revision: acoustics, transducers, pulse and beam properties, resolution, Doppler, artefacts, safety and common True/False traps.
Computed Tomography
Attenuation, Hounsfield units, helical acquisition, reconstruction, dose indices, artefacts and dual-energy CT.
Magnetic Resonance Imaging
Precession, relaxation, encoding, k-space, SNR trade-offs, artefacts and MRI safety.
Work five complete stems with no account, or sit an exam-length mock with a free account.
The Physics Bank is independent examination preparation. It is not affiliated with or endorsed by the Royal College of Radiologists. Exam rules change: always check the current RCR candidate guidance for your own sitting.
