Archimedes' Principle

What is Archimedes' Principle?

The buoyant force acting on an object submerged in a fluid equals the weight of the fluid the object displaces. A steel ship floats not because steel is light, but because its hollow hull displaces a volume of water heavy enough to equal the ship's total weight.

The five clues

Engineerdle #8 described Archimedes' Principle with five clues, revealed one at a time from hardest to most direct. Each clue points at a different property of the concept.

1. 01Supposedly discovered in a bathtub, followed by a famous shout of 'Eureka'.
2. 02It explains why a steel ship floats despite steel being denser than water.
3. 03The key isn't the material — it's the shape of the hull displacing water.
4. 04A submerged object feels an upward push equal to something specific.
5. 05The buoyant force on a submerged object equals the weight of fluid it displaces.

More Fluid Mechanics concepts

• Venturi EffectPuzzle #50
• ViscosityPuzzle #46
• Reynolds NumberPuzzle #41
• Newtonian FluidPuzzle #36
• Non-Newtonian FluidPuzzle #31
• Pascal's LawPuzzle #13