The buoyancy simulator graphically and diagrammatically represents the forces on a block immersed in a fluid. The density of the block and fluid can be changed, as well as the volume of the block. The amount of the block immersed in the fluid can also be changed to see how the tension and buoyant force changes with volume immersed. The "noise" can be adjusted to simulate lab data of the plot of tension versus weight of block immersed in fluid.