There is a very simple experiment that you can do at home to demonstrate Archimedes’ Principle, which relates to density and buoyancy. If you take an orange (with the peel intact) and drop it into a bucket of water, it floats. But if you peel the orange and do the same thing, the naked orange will sink to the bottom of the bucket -- even though the unpeeled orange is heavier. This is because the orange peel contains air pockets that make it less dense. And without the help of those air pockets, the peeled orange will sink, as it is much heavier than the volume of water that it displaces.
According to Archimedes:
- The density of an object relates to how closely its atoms are packed together. An orange’s lightweight rind gives the fruit buoyancy, much like an air-filled life jacket keeps a human afloat.
- The lightweight rind reduces the density of the orange as a whole. Density is the mass of an object relative to its volume.
- An aircraft carrier, for example, takes up more space than the volume of water that it displaces -- and so it floats, according to Archimedes’ Principle.