Buoyancy and Density Interactive Simulation

Archimedes' principle: an object in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces (F_b = ρV_displacedg). A less-dense object floats with only part of its volume submerged, an equal-density object is neutrally buoyant, and a denser object sinks. Students can change fluid density and object volume and compare what happens. Use it for physics inquiry with Grades 4–5, Middle School, and High School on a projector or student device.

Standards: NGSS 5-PS1-3

• Why a ship made of steel can float (its average density is less than water)
• How a floating object's density sets the fraction of its volume below the surface
• How the buoyant force changes with displaced volume
• Why objects feel lighter when held underwater
• Reading F_b = ρV_displacedg with your own fluid density and displaced volume

1. 1Predict how changing fluid density will affect the buoyant force, then test the prediction.
2. 2Use evidence from the live calculation and visual to explain the result.

Questions teachers ask