Sound familiar?

You can position a chest x-ray in your sleep. You know your landmarks, your technique charts, your protocols.

Then physics class starts, and something changes.

• The 15% rule shows up and you memorize it — but you couldn’t explain why it works if your life depended on it.
• Inverse square law, distance, density — you can recite the formula, but it doesn’t connect to what you’re actually doing at the console.
• Digital exposure indicators, latitude, CR vs. DR — it all blurs together into vocabulary you’re supposed to “just know.”
• Your textbook is 800 dense pages, and somehow none of them explain it the way your brain needs it explained.
• Registry day is coming, and the physics and radiobiology sections are the ones keeping you up at night — not because you’re not smart enough, but because nobody ever made it click.

If any of that sounds familiar, you’re not alone, and you’re not behind. You just haven’t had physics explained the right way yet.

The shift

Here’s the thing about x-ray physics: it isn’t actually that complicated. It’s just usually taught badly — as a wall of formulas and rules to memorize, disconnected from what’s happening inside the tube, at the detector, and on the image in front of you.

Radiography Physics Mastery teaches it the other way around.

Instead of handing you the 15% rule and moving on, it shows you what’s happening inside the x-ray tube that makes that rule true — so you don’t have to memorize it, you just understand it. Instead of a chapter on “digital imaging” that reads like a spec sheet, it walks you through what CR and DR are actually doing to the signal, and why that changes how you think about exposure and dose.

This approach comes from nearly a decade of teaching x-ray physics through How Radiology Works — first as blog posts, then as YouTube explanations watched by a growing community of students and techs. The book is what happens when years of “let me try explaining this a different way” gets distilled into one structured, ARRT-aligned resource, with hundreds of color illustrations doing the heavy lifting alongside the writing.

The goal isn’t to memorize more. It’s to finally get it — so the concepts stay with you long after registry day.

What’s inside

• X-ray production — how the tube actually generates the beam, and why tube current, kVp, and target angle matter the way they do
• Image formation & digital imaging — CR, DR, exposure indicators, latitude, and how digital systems changed the relationship between technique and image quality
• Radiation protection & radiobiology — dose, biological effects, and protection principles explained with context, not just rules to recall
• The math that actually matters — inverse square law, the 15% rule, and the other formulas that show up constantly, explained from first principles so they stop feeling arbitrary
• ~500 pages, hundreds of color illustrations — built to be looked at, not just read
• Structured around the ARRT Radiography Content Specifications — so what you study maps to what you’ll be tested on, without reading like a dry outline

Who this is for

This book is for you if you’re:

• A radiography student trying to make physics click before boards, not just survive the section
• A practicing tech who never quite felt solid on the physics behind what you do every day
• An educator looking for a clearer way to explain tube, detector, and dose concepts to students
• Someone who learns better from clear explanations and visuals than from dense, formula-heavy textbooks

This book is not:

• A full review program or a replacement for your radiography curriculum
• A giant question bank or exam-simulation tool
• A general ARRT registry review covering every content category — this is a physics and radiobiology companion, focused and deep on that one area where students tend to struggle most

Think of it as the resource that sits next to your program textbook and finally makes the physics chapters make sense.

About the author

Brian E. Nett, PhD, has spent close to a decade explaining x-ray physics to radiography students and techs — first through the How Radiology Works blog, then through a YouTube channel that’s grown to roughly 27,000 subscribers. Radiography Physics Mastery is the result of years of figuring out, through direct teaching, which explanations actually land and which ones don’t — assembled early mornings and weekends into the book he wished had existed when physics first felt impossible.

What readers are saying

From Amazon (Kindle and paperback).

Radiography Physics by Brian Nett is an exceptional cornerstone text for students and practitioners alike in medical imaging. Dr. Nett masterfully balances depth with clarity, presenting complex physical principles in a way that is both accessible to learners and sufficiently rigorous for advanced study. The book bridges the often-daunting gap between theoretical physics and its practical application in everyday radiographic practice, making it an invaluable resource for radiography students, educators, and clinical professionals.

— Sharon Mohammed, Amazon review

A great resource to understand medical physics. The CT concepts I am familiar with were well described and excellently presented. I wish it had been available a few decades ago. The author covered other modalities in a very understandable way. This demonstrates a great range, something for those experienced and accessible for the newcomer to the field.

— Bob Senzig, Amazon review

Studying radiography physics can be really intimidating — it pulls together math, physics, electronics, and image processing, all at once. What I liked most about this book is how it turns the learning process into a story with two heroes and “missions.” Instead of feeling like I was grinding through formulas, it felt more like progressing through challenges, which honestly made studying a lot more fun and less stressful.

— Henry, Amazon review

Radiography Physics Mastery is one of the most effective and approachable study resources I’ve come across for anyone preparing for the ARRT exam or looking to strengthen their understanding of imaging fundamentals. The author breaks down complex physics, digital imaging concepts, and radiation protection principles in a way that feels clear, logical, and genuinely helpful. The explanations are concise without sacrificing depth, and the structure makes it easy to build confidence as you go.

— Bret, Amazon review

Physics doesn’t have to be the section you dread.