Archimedes' Buoyancy Tank

Archimedes' Buoyancy Tank is an interactive 3D fluid-statics laboratory where students test Archimedes' principle by hand. A test block hangs from a calibrated overhead spring scale above an overflow tank filled to the spout. As students drag the block down into the fluid or click sample materials on the rack, water pours from the spout into a catch beaker on a digital balance. Live 3D vector arrows compare upward buoyant force F_b = rho_f g V_sub against downward gravity mg, while readouts display apparent weight on the spring scale, displaced water weight, buoyant force in newtons, and whether the object floats or sinks when released.

• Drag the Aluminum block halfway and then completely under water, and check that the decrease in Apparent weight equals the Displaced water weight in the catch beaker.
• Switch on Free float / sink and test Wood (600 kg/m³) and Ice (917 kg/m³) to see what percentage of each block stays submerged at equilibrium.
• Select Hollow Boat Hull (450 kg/m³) and compare its behavior with solid Iron (7870 kg/m³) to see why steel ships float.
• Increase Fluid density from 800 kg/m³ (oil) to 1400 kg/m³ (dense brine) and observe how the upward buoyant force arrow grows.
• Compare Aluminum, Iron, and Gold at the same 2.0 L volume when fully submerged to verify that buoyant force depends on displaced volume, not object density.

1. 1State Archimedes' principle and calculate buoyant force using F_b = rho_f g V_sub.
2. 2Explain why apparent weight in a fluid equals true weight minus buoyant force.
3. 3Predict whether an object will float, sink, or remain neutrally buoyant by comparing its average density to the fluid density.
4. 4Explain how hollowing out a dense material lowers its average density so a steel ship hull can float.

Questions teachers ask