✓ 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 is inverted (min=0 at top maps to "air" which is correct directionally, but the writing-mode/direction CSS combination with rtl causes the physical drag to be reversed — top of slider physically corresponds to water, bottom to air), and buoyancy force values are implausibly tiny (using cm³ as m³ yields ~0.0002 N instead of ~0.25 N, though V is converted via 1e-6 so the math is actually correct for cm³→m³ but the displayed 4-decimal result looks odd); otherwise a polished, feature-complete implementation with Heureka overlay, ripple/splash effects, and correct Archimedes physics.
Slider is inverted (min=0 at top maps to "air" which is correct directionally, but the writing-mode/direction CSS combination with rtl causes the physical drag to be reversed — top of slider physically corresponds to water, bottom to air), and buoyancy force values are implausibly tiny (using cm³ as m³ yields ~0.0002 N instead of ~0.25 N, though V is converted via 1e-6 so the math is actually correct for cm³→m³ but the displayed 4-decimal result looks odd); otherwise a polished, feature-complete implementation with Heureka overlay, ripple/splash effects, and correct Archimedes physics.