✓ 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
Physics values are directionally correct (same mass, gold 19.3 g/cm³ vs. gilded 10.5 g/cm³, larger displaced volume for gilded) but the water-level rise formula is arbitrary/dimensionally inconsistent, both crowns move identically (same fraction in water at all times so displacement ratio never diverges visually), and there is no smooth fall animation — crowns jump position instantly as the slider moves.
Physics values are directionally correct (same mass, gold 19.3 g/cm³ vs. gilded 10.5 g/cm³, larger displaced volume for gilded) but the water-level rise formula is arbitrary/dimensionally inconsistent, both crowns move identically (same fraction in water at all times so displacement ratio never diverges visually), and there is no smooth fall animation — crowns jump position instantly as the slider moves.