✓ Two crowns ✓ Same mass, different density ✓ Vertical slider ✓ Slider works ✓ Slider controls crowns — Slider direction correct ✓ Full slider range — Fall animation ✓ Water displacement ✓ Rising water level ✓ Splash effects — Physics correct ✓ Live mass value ✓ Live volume value ✓ Live density value ✓ Live displaced water — Gilded displaces more ✓ Heureka animation ✓ No external deps ✓ Light bg / dark text ✓ Self-contained HTML
Slider direction is inverted (value=0 is top=air which is correct by default, but the crown Y mapping places slider-max at bottom of viz which sends crowns DOWN into what should be water — however the water level barely rises meaningfully and both crowns move together at the same Y position, failing to show the gilded crown displacing more water; displaced water total combines both crowns without distinguishing them, and the displaced water value fed into waterLevelPercent uses an arbitrary nonsensical formula rather than true Archimedes physics.
Slider direction is inverted (value=0 is top=air which is correct by default, but the crown Y mapping places slider-max at bottom of viz which sends crowns DOWN into what should be water — however the water level barely rises meaningfully and both crowns move together at the same Y position, failing to show the gilded crown displacing more water; displaced water total combines both crowns without distinguishing them, and the displaced water value fed into waterLevelPercent uses an arbitrary nonsensical formula rather than true Archimedes physics.