Science experiment: Buoyancy.

AIMS:

o demonstrate what buoyancy is. Expanding the vocabulary….using an old float/sink technique to show a more mature concept of an old one. (If that makes sense, it does to me…)

Ever wondered what keeps big ships afloat on the ocean? Well, it’s buoyancy force!
This means that the fluid – in this case, the water- offsets the downward pull of gravity and pushes the boat up. The density of the object will determine its buoyancy.

To demonstrate this phenomenon, you’ll need:
a large container of water
two pieces of aluminium foil the same size.

Rolling up one piece of foil – making sure there is no air trapped inside- drop the piece in the water. It should sink.

Using the other piece of foil, pull the sides up in the shape of a boat. When placed in the water, this piece should float..

Though they weigh the same, the two pieces of foil reacted differently in the water due to their shape, because the shape changed their density.

Water also has density, and when you place an object- in this case our tin foil boat- on the water, it pushes aside some of the liquid. Basically, no matter what size the boat is, from a huge Ocean liner to the foil boat you just made, they are pretty much just containers full of air, and are less dense and lighter than the water, and this makes them float.

Experiment with different objects around your home. Try to guess each items buoyancy before dropping it in the water. You could make a chart of things with buoyancy and things that are too dense to float.