Halifax and Nova Scotia are defined by water – we’re surrounded by the ocean and countless lakes, rivers and streams. Most people see things that float in the water every day, but have you or your kids ever wondered how things float? Find out through quick and easy experiments at home!
To understand the ability to float (buoyancy), you need to understand displacement. If you put something solid in water (or air), it pushes that fluid out of the way. If the displaced water weighs as much as the boat, the boat will float! Boats need to push lots of water without being very heavy in order to stay afloat.
You can test this concept at home! Take a few everyday things lying around your house – newspaper, modelling clay, aluminum foil, or anything else you can manipulate – make them into different shapes and then try floating them. Next, try adding pennies to your “boats” for some added challenge, or try changing the shape of your “boats” to see if they make a difference.
For a bonus experiment, try it without water. You will need a helium balloon and small weights (taping pennies to the balloon strings works like a charm!). Helium (the second-lightest element) allows the balloon to float because the air displaced by the balloon is denser. If you get the weight pulling down just right (add one weight at a time; it can be tricky!), it will reach “neutral buoyancy” – in other words, it will hang perfectly without rising or falling (much), like a canoe on a calm lake.
We love the penny boat experiment at the Discovery Centre – it’s just one of the awesome public programs we have here every day. Bring the kids and come on down – see what else you can learn today!
For more great things to discover - visit the Discovery Centre on Barrington Street in Halifax, check out their website or join them on facebook.