Ever wondered why some things float while others sink?
Archimedes
Ever wondered why some things float while others sink?
Imagine you're at the beach, playing with a toy boat. You notice that when you place it in water, it floats, but when you put it in oil, it sinks. Why does this happen?
It's all about the balance between the weight of the boat and the water or oil it's in. The boat floats when the water pushes up against it more than its weight, but sinks in oil because the oil pushes up less.
Example
The toy boat weighs 1 kg. In water, it floats because the water pushes up with a force equal to 1 kg (the weight of the boat). In oil, it sinks because the oil's push up is less than 1 kg.
Remember this
Archimedes' principle explains that an object floats if the water's upward push (buoyancy) is equal to or greater than the object's weight.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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