This experiment demonstrates how water at different temperatures has different densities, creating beautiful layering effects. You'll see how warm and cold water interact and learn about density ...

It sounds like one of the easiest experiments possible: Take two cups of water: one hot, one cold. Place both in a freezer and note which one freezes first. Common sense suggests that the colder water ...

Decades after a Tanzanian teenager initiated study of the “Mpemba effect,” the effort to confirm or refute it is leading physicists toward new theories about how substances relax to equilibrium. It ...