Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Paper format. 98-Phys-B1 Radiation Physics, National Examination May 2015 — a three-hour open-book examination in which any non-communicating calculator is permitted. The cover page states the exam has 7 questions worth a total of 100 points, of which only 80 points' worth need be answered for full marks; every question and sub-part is nonetheless answered in full below so the paper remains a complete study resource. The cover page also invites the candidate to submit a written statement of any assumptions made where a question is open to interpretation — this licence is used in Question 1(a) (proton-mass vs. hydrogen-atom-mass convention), Question 3(d) (single effective attenuation coefficient for the polychromatic X-ray beam) and Question 5(c) (reading "the body" as the thyroid uptake compartment, consistent with the biological half-life given). The exam's own page-6 marking-scheme summary is internally inconsistent for two questions (it prints "15 points" for both Q2 and Q3, but their own per-sub-part marks, given beside each sub-part on the question pages, sum to 18 and 17 respectively); the sub-part marks are used below since only that reading makes the paper's own stated 100-point total add up exactly ($12+18+17+18+18+10+7=100$).
Reference texts. K. S. Krane, Introductory Nuclear Physics (nuclear masses and binding energy, radioactive decay); F. H. Attix, Introduction to Radiological Physics and Radiation Dosimetry (X-ray production, photon attenuation); J. R. Cember and T. E. Johnson, Introduction to Health Physics, 5th ed. (internal dosimetry, effective half-life, shielding, radiation survey practice); J. E. Turner, Atoms, Radiation, and Radiation Protection, 3rd ed. (radiation interactions, detectors, health-physics standards).
