I wonder why that twig is sitting on top of the water like that…
Yeah, but why does wood float?
There are two forces acting on the life jacket - its weight and the force of the water pushing upwards on it - the upthrust.
And if the weight is equal to or less than the upthrust, it floats?
And when something floats we say it's buoyant?
So if the weight of the object is more than the upthrust it sinks?
Well, I don't care much for buoyancy, but whatever floats your boat! Hahaha!
Oh come on, it wasn't that bad!
Floating and sinking
When something is in water, there are two forces acting on it. Its weight and the force of the water pushing up, the upthrust.
If the weight is equal to or less than the upthrust, it floats. Things that float are buoyant.
If the weight is greater than the upthrust, it sinks.
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