Every number carries the definition that produced it

Nuclear
Power

Two reference guides and 4 quizzes — 200 questions in all — covering the physics, the machines, radiation and risk, and where the industry actually stands. Written to be correct rather than reassuring or alarming: where credible sources disagree these pages show the disagreement instead of resolving it, and where a number depends on a definition they give the definition. Each quiz breaks your score down by theme, so a poor result tells you what to re-read.

QUESTIONS
200
Across 4 quizzes and 24 themes
REPEATS
Zero
Every set checked against all the others
GUESSABLE
No
Answer length carries no signal
TO PASS
80%
Earns a printable certificate
Start Here

How Nuclear Power Works

Fission and what 200 MeV really means, the chain reaction and why delayed neutrons are the only reason a reactor can be controlled, reactivity feedback and the sign that destroyed Chernobyl, moderators and coolants, control and the xenon pit, the decay heat curve that explains most of the plant, reactor types, the fuel cycle, radiation dose stated correctly, the genuine argument about low doses, defense in depth, and the three accidents counted carefully.

Open the physics guide
Companion Guide

Where Nuclear Power Stands

The world fleet and the two slogans that have outlived their accuracy, four institutions counting the US fleet four ways and why all four are right, the capacity factor improvement that made the fleet a third bigger with no new construction, license renewal to eighty years, the restarts that have not happened yet, what it costs to run an old plant against building a new one, 45U and what it actually does, and waste policy.

Open the industry guide

The Quizzes

In the order the guide covers them. Each one stands on its own — start wherever the subject interests you.

50 Questions

Fission and the Chain Reaction

What a fission event actually releases and how much of it arrives late, k-effective and why prompt neutrons alone could not be controlled, delayed neutrons and reactivity measured in dollars, the feedback signs, decay heat, and heat to power.

Fission Itself The Chain Reaction Delayed Neutrons and Control Margin Reactivity Feedback Decay Heat Heat to Power
Start • 6 themes
50 Questions

Reactors and the Fuel Cycle

Moderators and coolants and why the choice decides everything downstream, the six reactor families, control on three timescales including the xenon pit, enrichment levels, the fuel cycle from mine to dry cask, and reprocessing.

Moderators and Coolants Reactor Types Control Enrichment The Fuel Cycle Reprocessing and Waste Form
Start • 6 themes
50 Questions

Radiation and Safety

The four quantities that all get called radiation, background and the regulatory limits, deterministic and stochastic effects, the real argument about low doses, defense in depth and risk assessment, and the three accidents counted carefully.

Dose Units and Quantities Background and Limits Biological Effects The Low-Dose Argument Defense in Depth The Three Accidents
Start • 6 themes
50 Questions

The Fleet, Cost and Policy

The world fleet and two slogans that outlived their accuracy, four institutions counting the US fleet four ways, the capacity factor nobody discusses, license renewal and the restarts that have not happened, cost, and waste policy.

The World Fleet The US Fleet and How to Count It Capacity Factor and Uprates Renewal, Shutdowns and Restarts Economics Waste Policy and Who Is Building
Start • 6 themes
How these were built

Each quiz expands one part of a reference guide into 50 questions in six themes. Options are reshuffled every time you start, and every set was checked against all the others so no question is asked twice. One deliberate constraint runs through all of them: answer length carries no signal in either direction. Across all 200 questions the correct answer is the longest option 26 percent of the time and the shortest about as often, which is what chance would give you. Guarding only against the longest answer is how you end up with a set where picking the shortest wins.

Why the definitions matter here

Nearly every argument in this field that looks like a factual disagreement turns out to be two people quoting correctly measured numbers that measure different things: beta against beta-effective, thermal against net electrical, lower against higher heating value, licensed units against generators, one population boundary against another. These pages show both and name the difference. The three accidents are handled the same way: confirmed acute deaths, counted cancers in an identified cohort, and statistical projections from collective dose are three different questions, and no question here asks how many people died.