ARRT MRI (MR) Registry Exam Prep. The ARRT MRI coach built where the exam actually is: 53% of it is Image Production physics. Pulse-sequence parameters, the artifact board, and the safety numbers drilled at the real 8/10.5/53/28.5 weighting, by ear, with an honest scaled-75 bar. 200-question practice bank, every fact taught aloud with a memory hook, explained answers, review tests at the real passing bar. Your first module is free — no card required.