Exhibit No. 002 · Animation

Ball bouncing in a spinning hexagon

The physics test that went viral in early 2025: a ball with gravity and friction bouncing inside a rotating hexagon.

Prompt

> Write an HTML page (single file, canvas + JS) that shows a ball bouncing inside a spinning hexagon. The ball should be affected by gravity and friction, and it must bounce off the rotating walls realistically.

What it tests

Collision handling against moving walls — the wall velocity at the contact point has to be part of the bounce.

Origin

Flavio Adamo (original was a Python version) · 2025

Prompt wording adapted from the original.

Difficulty

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Results

Verdicts are our own assessment of each answer.

Claude Opus 5.5

Pass

Run on 2026-10-19Open the raw answer

Test conditions

Single attempt per test, no retries and no edits afterwards. Run inside a Claude Code agent session, which includes its own system prompt, rather than the raw API.

All results for Claude Opus 5.5

Run it yourself

Paste the prompt into the model or agent you want to test. Save the answer as a .html file and open it in a browser.

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