How to Master Which Breaks?
TLDR: Which Breaks? puts two absurd things against each other · a steel bat against a million bottles, a litre of lava against a tonne of ice · and asks which one gives way first. Every verdict is settled by real physics with real numbers, and the reveal shows the working. The winning habit is to stop asking which side is more impressive and start asking which single quantity decides it. Nine contests in ten turn on energy, heat, pressure or fatigue, and the impressive side is usually the one that runs out.
What a round gives you
Two sides, each named with a quantity attached · “one litre of lava at 1,100 degrees Celsius”, “a tonne of ice”. You pick which one fails. Then the reveal works the verdict out with the real constants: the latent heat of fusion of ice at 334,000 joules per kilogram, the specific heat of water at 4,186 joules per kilogram per kelvin, steel’s fatigue endurance limit, pressure rising one atmosphere every ten metres of water.
Read the reveal even when you are right. The answer is one bit. The two or three numbers that decided it are the whole game, and they transfer · the round that teaches you the latent heat of ice hands you the next four ice contests.
The four questions that settle most contests
Is this about energy? A hot thing melting a cold thing is a budget. Multiply mass by the energy each kilogram needs, and compare it against what the hot side actually carries. Lava is dramatic and there is not much of it; ice is boring and there is a tonne.
Is this about heat capacity? Water absorbs an enormous amount of heat for very little temperature rise. Anything fighting a large mass of water is fighting a heat sink, and usually loses.
Is this about pressure? Pressure grows about one atmosphere every ten metres of depth, and a shape that resists it from outside fails suddenly rather than gradually. Depth contests almost always go to whatever is solid.
Is this about fatigue? A material has a stress it can take once and a much lower stress it can take a million times. A contest phrased as “again and again” is a fatigue question, and the answer is almost never the same as the one-shot answer.
Find the quantity, then find the amount: name which of the four it is, then ask which side brings more of the thing that matters. “One litre” against “a tonne” is not a fair fight whatever the litre is made of. The adjective is the distraction and the mass is the answer.
Why the impressive side usually loses
The pool is built so that the counter-intuitive verdicts sit at the top tiers, and there is a reason they feel wrong. Lava, blowtorches, bullets and rifle rounds are vivid, and vividness has nothing to do with quantity. A blowtorch is very hot and delivers a few kilowatts; an anvil is cold and holds tens of kilograms of steel with a heat capacity to match.
Caution · the shock of the reveal is the lesson, not a trick. Every entry is defensible with a worked argument, and ideas that could not be justified numerically were dropped when the pool was written. If a verdict surprises you, the reveal will name the constant you were not weighing · that is the round doing its job.
What difficulty changes
Difficulty scales how counter-intuitive the verdict is, not how hard the arithmetic is.
- Easy · intuitive once you think for a moment. A warm bath against an ice cube.
- Medium · genuinely feels like a coin flip. A blowtorch against an anvil.
- Hard · the “wait, really?” rounds, where most people confidently pick the side that survives.
Play easy until the four questions are automatic. The hard tier is not harder physics · it is the same four questions against a stronger instinct. Build the habit where your instinct is not fighting you.
Say the deciding quantity out loud before you pick. “This is a heat budget.” “This is fatigue.” If you cannot name it, you are picking on vividness, and vividness loses.
Watch for the word that hides a count. “A million bottles”, “three metres of water”, “fifty cycles”. A number in the phrasing is almost always the number that decides the round.
A practice path
Phase 1 · name the quantity. Easy tier. Before each pick, say which of the four questions it is. Goal: stop answering on impression.
Phase 2 · estimate the budget. Medium tier. Guess the rough size of the deciding number before the reveal. Goal: build a feel for the constants.
Phase 3 · trust the arithmetic over the picture. Hard tier. When your gut and your estimate disagree, go with the estimate. Goal: the whole point of the game.
Phase 4 · reuse. Notice when a round uses a constant you met earlier. Goal: the pool is finite and the physics repeats.
The mastery metric
You have mastered Which Breaks? when the reveal stops surprising you · not because you memorised the pool, but because you name the deciding quantity before you pick, and the impressive side has stopped being the one you reach for.
Which Breaks?
Two absurd contests · one side breaks, melts or gives up. Predict it, then see the physics math that settles it
Play nowWorks on any device.