Energy Runs Hot to Cold

You'll learnwhich way energy goes when two systems touch, what actually decides it, and what has really stopped once everything reads one temperature.

A hot flask holding 76 joules touches a cool room holding 4.6 million. The energy leaves the flask anyway, because direction is decided by temperature, not by totals. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · HEAT AS TRANSFER · DIRECTION FROM TEMPERATURE · NET VERSUS GROSS · v2

two boxes, one shared wall · every exchange conserves the pair exactly

Before you start

What you're looking at

Two boxes of gas touching along a shared wall, one hot and one cool. Each dot is a molecule.

The question

Which way does energy go when the boxes touch, and what stops once they reach one temperature?

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